 |
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
| Datasheet File OCR Text: |
| copyright?2011 fujitsu semiconductor limited all rights reserved 2011.12 fujitsu semiconductor data sheet ds405-00007-1v0-e fujitsu semiconductor confidential assp for power management applications 2ch dc/dc converter ic with pfm/ pwm synchronous rectification mb39a214a ? description mb39a214a is a n-ch/ n-ch synchronous rectification type 2ch buck dc/dc converter ic equipped with a bottom detection comparator for low output voltage ripple. it supports low on-duty operation to allow stable output of low voltages when there is a large difference between input and output voltages. it also allows the high switching frequency setting, enabli ng the downsized peripheral circuits and low-cost configuration. mb39a214a realizes ultra-rapid res ponse and high efficiency with built-in enhanced protection features. it is most suitable for the power supply for asic or fpga core, input/output devices, or memory. ? features y high efficiency y frequency setting by internal preset function : 310 khz, 620 khz, 1 mhz y high accuracy reference voltage : 0.7% (ta = + 25 c) y v in input voltage range : 6 v to 28 v y output voltage setting range : 0.7 v to 5.3 v y possible to select the automatic pfm/pwm selection mode or pwm-fixed mode y paf frequency limitation function (prohi bit audio frequency) : > 30 khz (min) y built-in boost diode, external fly-back diode not required y built-in discharge fet y built-in over voltage protection function y built-in under voltage protection function y built-in over temperature protection function y built-in over current limitation function y soft-start circuit without load dependence y current sense resistor not required y built-in synchronous rectification type output steps for n-ch mos fet y standby current : 0 a (typ) y package : tssop24 (4.4 mm 6.5 mm 1.2 mm [max]) ? applications y digital tv y photocopiers y stb y bd, dvd players/recorders y projectors etc.
2 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? pin assignment (top view) 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 drvh1 lx1 drvl1 pgnd ilim1 vcc vb mode ilim2 drvl2 lx2 drvh 2 BST1 en1 vout1 fb1 cs1 gnd freq cs2 fb2 vout2 en2 bst2 (fpt-24p-m09) 3 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? pin descriptions pin no. pin name i/o description 1 BST1 ? ch1 boost capacitor connection pin. 2 en1 i ch1 enable pin. 3 vout1 i ch1 input pin for dc/dc output voltage. 4 fb1 i ch1 input pin for feedback voltage. 5 cs1 i ch1 soft-start time setting capacitor connection pin. 6 gnd ? ground pin. 7 freq i frequency switching signal input pin. freq : gnd short switching frequency 310 khz freq : open switching frequency 620 khz freq : vb short switching frequency 1 mhz 8 cs2 i ch2 soft-start time setting capacitor connection pin. 9 fb2 i ch2 input pin for feedback voltage. 10 vout2 i ch2 input pin for dc/dc output voltage. 11 en2 i ch2 enable pin. 12 bst2 ? ch2 boost capacitor connection pin. 13 drvh2 o ch2 output pin for external high-side fet gate drive. 14 lx2 ? ch2 inductor and external high-side fet source connection pin. 15 drvl2 ? ch2 output pin for external low-side fet gate drive. 16 ilim2 i ch2 over current detection level setting voltage input pin. 17 mode i dc/dc control mode switching signal input pin. mode : gnd short pfm/pwm mode : open pfm/pwm, paf mode : vb short pwm fixed 18 vb o internal circuit bias output pin. 19 vcc i power input pin for control and output circuits. 20 ilim1 i ch1 over current detection level setting voltage input pin. 21 pgnd ? ground pin for output circuit. 22 drvl1 o ch1 output pin for external low-side fet gate drive. 23 lx1 ? ch1 inductor and external high-side fet source connection pin. 24 drvh1 o ch1 output pin for external high-side fet gate drive. 4 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? block diagram 5a 1a 2 a 2 a 450 k ? 450 k ? vin (6 v to 28 v ovp uvp uvp2 uvp1 ovp2 ovp1 ref1 0.7 v ref1 1.15v /en1 /uvlo(otp) /en1 otp uvp ref1 (0.7 v) t on generator vcc en1 en2 vcc vb vb 4 : 1 25 ? 5 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? absolute maximum ratings rating parameter symbol condition min max unit vcc pin input voltage v vcc vcc pin ? 0.3 + 30 v bst pin input voltage v bst BST1, bst2 pins ? 0.3 + 36 v lx pin input voltage v lx lx1, lx2 pins ? 1 + 30 v voltage between bst and lx v bst-lx ? ? 0.3 + 7 v en pin input voltage v en en1, en2 pins ? 0.3 + 30 v v fb fb1, fb2 pins ? 0.3 vb + 0.3 v v vout vout1, vout2 pins ? 0.3 + 7 v v ilim ilim1, ilim2 pins ? 0.3 vb + 0.3 v v cs cs1, cs2 pins ? 0.3 vb + 0.3 v v freq freq pin ? 0.3 vb + 0.3 v input voltage v mode mode pin ? 0.3 vb + 0.3 v output current i out drvh1, drvh2 pins, drvl1, drvl2 pins ? 60 ma power dissipation p d ta + 25 c ? + 1282 mw storage temperature t stg ? ? 55 + 125 c warning: semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc.) in excess of absolute maximum ratings. do not exceed these ratings. 6 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? recommended operating conditions value parameter symbol condition min typ max unit vcc pin input voltage v vcc vcc pin 6 ? 28 v bst pin input voltage v bst BST1, bst2 pins ? ? 34 v en pin input voltage v en en1, en2 pins 0 ? 28 v v fb fb1, fb2 pins 0 ? vb v v vout vout1, vout2 pins 0 ? 5.5 v v ilim ilim1, ilim2 pins 0 ? 2 v v freq freq pin 0 ? vb v input voltage v mode mode pin 0 ? vb v peak output current i out drvh1, drvh2 pins, drvl1, drvl2 pins duty 5% (t = 1/f osc duty) ? 1200 ? + 1200 ma operating ambient temperature ta ? ? 30 + 25 + 85 c warning: the recommended operating conditions are requi red in order to ensure the normal operation of the semiconductor device. all of the device's electrical characteristics are warranted when the device is operated within these ranges. always use semiconductor devices within th eir recommended operating condition ranges. operation outside these ranges may adversely affect reliability and could result in device failure. no warranty is made with respect to uses, operating conditions, or combinations not represented on the data sheet. users considering application out side the listed conditions are advised to contact their representatives beforehand. 7 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? electrical characteristics (ta = + 25c, vcc = 12 v, en1, en2 = 5 v) value parameter symbol pin no. condition min typ max unit output voltage v vb 18 vb = 0 a 5.04 5.20 5.36 v input stability line 18 vcc = 6 v to 28 v ? 10 100 mv load stability load 18 vb = 0 a to ? 1 ma ? 10 100 mv bias voltage block [vb reg.] short-circuit output current i os 18 vb = 0 v ? 145 ? 100 ? 75 ma v tlh 18 vb pin 4.0 4.3 4.6 v threshold voltage v thl 18 vb pin 3.7 4.0 4.3 v under voltage lockout protection circuit block [uvlo] hysteresis width v h 18 vb pin ? 0.3* ? v charge current i cs 5,8 cs1, cs2 = 0 v ? 1.5 ? 1.0 ? 0.75 a electrical discharge resistance r d 3,10 en1, en2 = 0 v, vout1, vout2 0.15 v ? 25* ? ? soft-start/ discharge block [soft start, discharge] discharge end voltage v vovth 3,10 en1, en2 = 0 v, vout1, vout2 pins ? 0.2* ? v t on11 24 freq pin gnd connection vcc = 12 v, vout1 = 1.5 v 430 538 646 ns on time (preset value 1) t on21 13 freq pin gnd connection vcc = 12 v, vout2 = 1.5v 320 400 480 ns t on12 24 freq pin open vcc = 12 v, vout1 = 1.5 v 210 263 316 ns on time (preset value 2) t on22 13 freq pin open vcc = 12 v, vout2 = 1.5 v 160 200 240 ns t on13 24 freq pin vb connection vcc = 12 v, vout1 = 1.5 v 130 163 196 ns on time (preset value 3) t on23 13 freq pin vb connection vcc = 12 v, vout2 = 1.5 v 100 125 150 ns t onmin11 24 freq pin gnd connection vcc = 12 v, vout1 = 0v ? 136 191 ns minimum on time (preset value 1) t onmin21 13 freq pin gnd connection vcc = 12 v, vout2 = 0v ? 103 145 ns t onmin12 24 freq pin open vcc = 12 v, vout1 = 0v ? 77 108 ns minimum on time (preset value 2) t onmin22 13 freq pin open vcc = 12 v, vout2 = 0v ? 58 82 ns t onmin13 24 freq pin vb connection vcc = 12v, vout1 = 0v ? 55 77 ns minimum on time (preset value 3) t onmin23 13 freq pin vb connection vcc = 12 v, vout2 = 0v ? 43 61 ns on/off time generator block [t on generator] minimum off time t offmin 24, 13 ? ? 410 535 ns 8 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e value parameter symbol pin no. condition min typ max unit threshold voltage v th 4, 9 ta = + 25 c 0.695 0.700 0.705 v fb pin input current i fb 4, 9 fb1, fb2 = 0.7 v ? 0.1 0 + 0.1 a error comparison block [error comp.] vout pin input current i vo 3,10 vout1, vout2 = 1.5 v ? 6.0 8.6 a over current detection offset voltage v offilim 21 to 23 21 to 14 pgnd ? lx1, lx2 ilim1, ilim2 = 500 mv ? 30 0 + 30 mv ilim pin current i ilim 20,16 ilim1, ilim2 = 0 v ? 6 ? 5 ? 4 a over current detection block [ilim comp.] ilim pin current temperature slope t ilim 20,16 ta = + 25 c ? 4500* ? ppm/ c over-voltage detecting voltage v ovp 4, 9 for ref1, ref2 voltage 110 115 120 % hysteresis width v hovp 4, 9 ? ? 5* ? % over- voltage protection circuit block [ovp comp.] detection delay time t ovp ? ? 10 15 20 s under-voltage detecting voltage v uvp 4, 9 for ref1, ref2 voltage 65 70 75 % hysteresis width v huvp 4, 9 ? ? 10* ? % under- voltage protection circuit block [uvp comp.] detection delay time t uvp ? ? 100 150 200 s t otph ? ? ? 150* ? c over- temperature protection circuit block [otp] protection temperature t otpl ? ? ? 125* ? c r oh 24,13 drvh1, drvh2 = ? 100 ma ? 4 6 ? high-side output on-resistance r ol 24,13 drvh1, drvh2 = 100 ma ? 1 1.5 ? r oh 22,15 drvl1, drvl2 = ? 100 ma ? 4 6 ? low-side output on-resistance r ol 22,15 drvl1, drvl2 = 100 ma ? 1 1.5 ? output source current i source 24,13 22,15 lx1, lx2 = 0 v, BST1, bst2 = vb drvh1, drvh2 = 2.5 v duty 5% ? ? 0.5* ? a output sink current i sink 24,13 22,15 lx1, lx2 = 0 v, BST1, bst2 = vb drvh1, drvh2 = 2.5 v duty 5% ? 0.9* ? a lx1, lx2 = 0 v, BST1, bst2 = vb drvl1, drvl2-low to drvh1, drvh2-on 15 25 35 ns output block [drv] dead time t d 24 to 22 13 to 15 lx1, lx2 = 0 v, BST1, bst2 = vb drvh1, drvh2-low to drvl1, drvl2-on 35 50 65 ns 9 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e value parameter symbol pin no. condition min typ max unit bst diode voltage v f 1,12 i f = 10 ma 0.75 0.85 0.95 v output block [drv] bias current i bst 1,12 lx1, lx2 = 0 v, BST1, bst2 = 5.2 v 11 15 22 a preset value 1 conditions v freq1 7 freq pin: gnd connection 0 ? 0.2 v preset value 2 conditions v freq2 7 freq pin: open 0.6 ? 1.2 v preset value 3 conditions v freq3 7 freq pin: vb connection 2.4 ? vb v switching frequency control block [freq] freq pin output voltage v freq 7 freq = open 0.63 0.9 1.17 v pfm/pwm mode conditions paf function negate v pfm1 17 mode pin: gnd connection 0 ? 0.2 v pfm/pwm mode conditions paf function assert v pfm2 17 mode pin : open 0.6 ? 1.2 v pwm-fixed mode conditions v pwm 17 mode pin : vb connection 4.6 ? vb v paf frequency f paf ? ta = ? 30 c to + 85 c 30 45 ? khz pfm control circuit block [mode] mode pin voltage v mode 17 mode = open 0.63 0.9 1.17 v on condition v on 2, 11 en1, en2 pins 2.64 ? ? v off condition v off 2, 11 en1, en2 pins ? ? 0.66 v hysteresis width v h 2, 11 en1, en2 pins ? 0.4* ? v enable block [en1 , en2] input current i en 2, 11 en1, en2 = 5v 11 15 22 a standby current i ccs 19 en1, en2 = 0v ? 0 10 a power supply current during idle period i cc1 19 lx1, lx2 = 0 v BST1, bst2 : vb connection fb1, fb2 = 0.75 v ? 600 860 a power supply current power supply current during operation i cc2 19 lx1, lx2 = 0v BST1, bst2 : vb connection fb1, fb2 = 0.6 v ? 1200 1700 a *: this parameter is not be specified. this should be used as a reference to support designing the circuits. 10 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? typical characteristics power dissipation vs. operating ambient temperature power dissipation p d (mw) 0 500 1000 1500 2000 -50 -25 +0 +25 +50 +75 +100+12 5 1282 operating ambient temperature ta ( c) vb bias voltage vs. operating ambient temperature vb bias voltage vs. vb bias output current vb bias voltage v vb (v) 5.00 5.04 5.08 5.12 5.16 5.20 5.24 5.28 5.32 5.36 5.40 -40 -20 0 +20 +40 +60 +80 +100 vcc=12v i vb =0a vb bias voltage v vb (v) 5.0 5.1 5.2 5.3 5.4 -30 -25 -20 -15 -10 -5 0 vcc=6v vcc=12v vcc=28v operating ambient temperature ta ( c) vb bias output current i vb (ma) error comp. threshold voltage vs. operating ambient temperature ilim pin current vs. oper ating ambient temperature error comp. threshold voltage v th (v) 0.695 0.696 0.697 0.698 0.699 0.700 0.701 0.702 0.703 0.704 0.705 -40 -20 0 +20 +40 +60 +80+100 ilim pin current i ilim (a) -6.0 -5.5 -5.0 -4.5 -4.0 -3.5 -40 -20 0 +20 +40 +60 +80 + 100 operating ambient temperature ta ( c) operating ambient temperature ta ( c) ta = +25 c 11 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e drvh1 on time vs. operating ambient temperature drvh2 on time vs. operating ambient temperature drvh1 on time t on1 (ns) 100 150 2 00 2 50 300 350 4 00 4 50 500 550 600 650 700 -40 -20 0 +20 +40 +60 +80 +100 vcc=12v vout1=1.5v freq=gnd freq=open freq=vb drvh2 on time t on2 (ns) 50 100 150 200 250 300 350 400 450 500 -40 -20 0 +20 +40 +60 +80 +100 vcc=12v vout2=1.5v freq=gnd freq=open freq=vb operating ambient temperature ta ( c) operating ambient temperature ta ( c) drvh1 minimum on time vs. input voltage drvh2 minimum on time vs. input voltage drvh1 minimum on time t onmin1 (ns) 0 50 100 150 200 250 5 1015202530 freq=gnd freq=open freq=vb drvh2 minimum on time t onmin1 (ns) 0 50 100 150 200 5 1015202530 freq=gnd freq=open freq=vb input voltage v in (v) input voltage v in (v) drvh1 minimum on time vs. operating ambient temperature drvh2 minimum on time vs. operating ambient temperature drvh1 minimum on time t onmin1 (ns) 40 60 80 100 120 140 160 180 -40 -20 0 +20 +40 +60 +80 +100 vcc=12v vout1= 0 v freq=gnd freq=open freq=vb drvh2 minimum on time t onmin2 (ns) 20 40 60 80 100 120 140 -40 -20 0 +20 +40 +60 +80 +100 vcc=12v vout2=0 v freq=gnd freq=open freq=vb operating ambient temperature ta (c) operating ambient temperature ta (c) ta = + 25c ta = + 25c 12 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e minimum off time vs. input voltage minimum off time vs. operating ambient temperature minimum off time t offmin (ns) 200 250 300 350 400 450 500 550 600 5 1015202530 minimum off time t offmin (ns) 200 250 300 350 4 00 4 50 500 550 600 -40 -20 0 +20 +40 +60 +80 +100 vcc=12v input voltage v in (v) operating ambient temperature ta (c) dead time vs. operating ambient temperature bootstrap diode i f vs. v f dead time (ns) 20 25 3 0 3 5 4 0 4 5 50 55 6 0 -40 -20 0 +20 +40 +60 +80 +100 lx=0v v bst =vb t d1 t d2 i f current i f (ma) 0.001 0.01 0.1 1 10 100 0.2 0.4 0.6 0.8 1 1.2 operating ambient temperature ta (c) v f voltage v f (v) t d1 : period from drvl off to drvh on t d2 : period from drvh off to drvl on ta = - 30c ta =+25c ta =+ 85c ta = + 25c 13 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? function bottom detection comparator system for low output voltage ripple the bottom detection comparator system for low output voltage ripple determines the on time (t on ) using the input voltage (v in ) and output voltage (v out ) to hold the on state to a specified period. during the off period, the reference voltage (intref) is compared with the feedback voltage (fb) using the error comparator (error comp.). when the feedback voltage (fb) is below the reference voltage (intref) , rs-ff is set and the on period starts again. switching is repeated as described above. error comp. is used to compare the reference voltage (intref) with the f eedback voltage (fb) to control the off-duty condition in order to stabilize the output voltage. this system adds the inductor current slope detected during the synchronous rectification period (t off ) to the reference voltage (intref) , and generates an output voltage slope during the off period, which is essential for the bottom detection comparator system, in the ic. this enables the stable control operations under the low output voltage ripple conditions. y circuit diagram bias t on generator slope detector drive logic intref v ref v in i l s v out bias reg. lo-side drive fb - + rs-ff 14 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (1) bias voltage block (vb reg.) the 5.2 v (typ) bias voltage is generated from the vcc pin voltage for the control, output, and boost circuits. when either or both of the en1 pin (pin 2) and en2 pin (pin 11) are set to the ?h? level, the system is restored from the standby state to supply the bias voltage from the vb pin (pin 18). (2) on/off time generator block (t on generator) this block contains a capacitor for timing setting and a resistor for timing setting and generates on time (t on ) which depends on input voltage and output voltage. the switching frequency can be switched by setting the freq pin (pin 7) to any one of gnd c onnection, open, and vb connection. on time for each ch is obtained from the following formula. 15 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (4) starting sequence when the en1 pin (pin 2) or en2 pin (pin 11) is set to the ?h? level, the bias voltage is supplied from the vb pin. if the voltage of the vb pin exceeds the uvlo threshold voltage, the dc/dc converter starts operations and carries out the soft start. the soft start is a function used to prevent a rush current when the power is started. activating the soft start initiates charging of the capacito r connected to the cs1 pin (pin 5) and cs2 pin (pin 8) and inputs the lamp voltage to the error comp arator (error comp.) of each channel. the dc/dc converter generates the output voltage according to that la mp voltage. this results in the soft start operation that does not depend on the output load. the over vo ltage protection (ovp) and under voltage protection (uvp) functions are disabled while the soft start is active. 16 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (5) dc/dc converter stop sequence (discharge, standby) when the en1 pin (pin 2) or en2 pin (pin 11) is set to the ?l? level, the output capacitor is discharged using the discharge fet (r on 25 ? ) in the ic. if the voltage of the vout1 pin (pin 3) and vout2 pin (pin 10) is below 0.2 v (typ) by discharging the output capacitor, the ic stops discharge operation. further, if both the en1 and en2 pins are set to the ?l? level, the ic also stops the output of the vb pin and enters the standby state after detecting uvlo. the current of the vcc pin (i vcc ) is then 10 a (max). 17 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (7) over current limitation (ilim) this function limits the output current when it has increased, and protects devices connected to the output. this function detects the inductor current i l from the electromotive force of the low-side fet on-resistance r on , and compares this voltage with the 1/5-time value of the voltage v ilim of the ilim1 pin (pin 20) and ilim2 pin (pin 16) on a cyclically, using ilim comp . until this voltage falls below the over current limit value, the high-side fet is held in the off state. after the voltage has fallen below the limit value, the high-side fet is placed into the on state. this limits the lower bound of the inductor current and also restricts the over current. as a result, it becomes operation that the output voltage droops. the over current limit value is set by connecting the resistor to the ilim pin. the ilim pin supplies the constant current of 5 a (typ) . however, the current value has a temperature slope up to 4500 ppm/c to compensate the temperature dependence characteristics of the low-side fet on-resistance. i l v out drvh drvl (i out1 ) output voltage setting value keep the off state of the high-side fet until the detection value is gained. over current limit operation normal operation v ilim ilim detection value (r on i l = 5 ) 18 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (8) over voltage protection (ovp) this function stops the output voltage when the output voltage has increased, and protects devices connected to the output. 1. using ovp comp, this function makes a comparison between the voltage which is 1.15 times (typ) of the internal reference voltage intref1 and intref 2 (0.7 v), and the feedback voltage for the fb1 pin (pin 4) and the fb2 pin (pin 9). 2. if the feedback voltage mentioned in 1 detects th e higher state by 15s (typ) or more, the operations below will be performed. y set the rs latch. y set the drvh1 pin (pin 24) and the drvh2 pin (pin 13) to the ?l? level. y set the drvl1 pin (pin 22) and the drvl2 pin (pin 15) to the ?h? level. these operations fix the high-side fet to the off st ate and the low-side fet to the on state for both channels of the dc/dc converter, and stops switching (latch stop).the over-voltage protection state can be cancelled by setting both the en1pin (pin 2) and en2 pi n (pin 11) to the ?l? level or reducing the vcc power once until the bias voltage (vb) falls below v thl of uvlo. 19 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (9) under voltage protection (uvp) this function stops the output voltage when the output voltage has lowered, and protects devices connected to the output. 1. using uvp comp, this function makes a comparison between the voltage which is 0.7 times (typ) of the internal reference voltage ref1, ref2 (0.7 v), a nd the feedback voltage for the fb1 pin (pin 4) and the fb2 pin (pin 9). 2. if the feedback voltage mentioned in 1 detects the higher state by 150s (typ) or more, the operations below will be performed. y set the rs latch. y set the drvh1 pin (pin 24) and the drvh2 pin (pin 13) to the ?l? level. y set the drvl1 pin (pin 22) and the drvl2 pin (pin 15) to the ?l? level. these operations fix the high-side fet to the off st ate and the low-side fet to the off state for both channels of the dc/dc converter, and stops switching (l atch stop). the discharge operation is then carried out to discharge the output capacitor (the discharge ope ration continues until the state of the under-voltage protection is released). the under-voltage protection state ca n be cancelled by setting both the en1 pin (pin 2) and en2 pin (pin 11) to the ?l? level or reducing the vcc power on ce until the bias voltage (vb) falls below v thl of uvlo. 20 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (10) over temperature protection (otp) the over-temperature protection circuit block (otp) provi des a function that prevents the ic from a thermal destruction. if the junction temperature reaches + 150 c, the drvh1 pin (pin 24) and drvh2 pin (pin 13) are set to the ?l? level, and the drvl1 pin (pin 22 ) and drvl2 pin (pin 15) are set to the ?l? level. this fixes the high-side and low-side fets to the off-sta te, of both channels in the dc/dc converter, causing switching to be stopped. the discharge operation is then carried out to discharge the output capacitor (the discharge operation continues until the state of the over-temperature protection is released). if the junction temperature drops to + 125 c, the soft start is reactivated. (restored automatically.) (11) operation mode in the pwm-fixed mode, the system acts by the switching frequency specified with the freq pin regardless of the load. in the automatic pfm/pwm selection mode, the switching frequency is reduced at low load, for enhancing the conversion efficiency characteristics. this fu nction detects 0 a of the inductor current from the electromotive force of the low-side fet on resistan ce when the low-side fet on state, and places the low-side fet into the off state. this idle period continued until the output voltage decreased, this results the switching frequency being reduced automatically depend ing on the load current when the inductor current is below the critical current. the system acts by the switching frequency specified with the freq pin, when the inductor current exceeds the critical current. for automatic pfm/pwm selection mode with paf function, the switching frequency at low load is held to 30 khz (min) or more. the operation mode can be switched by setting the mode pin (pin 17) to any one of gnd connection, open, and vb connection. y pwm-fixed mode i outx i lxx v lxx 0 a y automatic pfm/pwm selection mode i outx i lxx v lxx 0 a switching frequency reduced inductor current in the opposite direction x : each channel number 21 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e y enable function table en1 pin en2 pin dc/dc converter (ch1) dc/dc converter (ch2) l l off off h l on off l h off on h h on on y dc/dc control mode function table mode pin dc/dc control gnd connection automatic pfm/pwm selection mode open automatic pfm/pwm selection mode with paf function vb connection pwm-fixed mode y switching frequency control function table freq pin switching frequency gnd connection f osc1 230 khz, f osc2 310 khz open f osc1 460 khz, f osc2 620 khz vb connection f osc1 750 khz, f osc2 1000 khz y protection function table the following table shows the state of the vb pin (pin 18), the drvh1 pin (pin 24), the drvh2 pin (pin 13), the drvl1 pin (pin 22), the drvl2 pin (pin 15) when each protection function operates. output of each pin after detection protection function detection condition vb drvh1, drvh2 drvl1, drvl2 dc/dc output dropping operation under voltage lockout protection (uvlo) vb < 4.0 v ? l l natural electric discharge over-current limitation (ilim) v pgnd - v lx1 , v lx2 > v ilim1 , v ilim2 5.2 v switching switching the voltage is dropped by the constant current over voltage protection (ovp) v fb1 , v fb2 > intref1, intref2 1.15 (15 s or higher) 5.2 v l h 0 v clamping under voltage protection (uvp) v fb1 , v fb2 > intref1, intref2 0.7 (150 s or higher) 5.2 v l l electrical discharge by discharge function over temperature protection (otp) tj > + 150 c 5.2 v l l electrical discharge by discharge function enable (en) en1, en2: h : l (v out1 , v out2 > 0.2 v) 5.2 v l l electrical discharge by discharge function 22 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? i/o pin equivalent circuit diagram vb fb1 fb2 en1 en2 gnd gnd mode gnd vb vb vb vcc ilim1 ilim2 vout1 vout2 gnd gnd pgnd vb frwq gnd en1, en2 pins fb1, fb2 pins esd protection element freq pin mode pin ilim1, ilim2 pins vout1, vout2 pins esd protection element 23 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e vb vb BST1 bst2 lx1 lx2 vcc gnd pgnd pgnd pgnd vb drvl1 drvl2 drvh1 drvh2 vb gnd vcc cs1 cs2 gnd drvl1, drvl2 pins cs pin drvh1, drvh2, BST1, bst2, lx1, lx2 pins vb pin vcc pin 24 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? example application circuit vin vin vin vin pgnd pgnd vout1 pgnd vout2 1.0 v, 7 a 1.8 v, 7 a mb39a214a 12 v + + vout1 fb1 en1 cs1 ilim1 mode freq vout2 en2 cs2 en2 en1 c13 c12 c7 c8 r6 r4 r3-2 r3-1 r1-2 r1-1 r5 r2 gnd pgnd drvl2 lx2 drvh2 bst2 drvl1 lx1 drvh1 BST1 vb vcc ilim2 fb2 3 19 18 1 24 23 12 13 14 15 21 2 1 q3 q3 q1 56 7 4 3 78 2 1 q1 56 4 3 l1 l2 c5 c1-1 c1-2 c2-1 c3-1 c6 c3-2 c4-1 c4-3 c2-3 8 22 2 5 4 20 17 7 10 9 11 8 16 6 25 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? part list component item specification vendo r package part number remarks q1 n-ch fet v ds = 30 v, i d = 9 a, 5.4 a, r on = 34 m ? , 13 m ? renesas sop8 pa2758 dualtype (2elements) q3 n-ch fet v ds = 30 v, i d = 9 a, 5.4 a, r on = 34 m ? , 13 m ? renesas sop8 pa2758 dualtype (2elements) l1 inductor 1 h (18 a) nec tokin - mpc1055l1r0 l2 inductor 1.5 h (12.4 a) nec tokin - mplc1040l1r5 c1-1 ceramic capacitor 10 f (25 v) murata 3216 grm31cb31e106k c1-2 ceramic capacitor 10 f (25 v) murata 3216 grm31cb31e106k c2-1 poscap 220 f (2 v) sanyo d case 2tplf220m6 c2-3 ceramic capacitor 1000 pf (50 v) tdk 1608 c1608jb1h102k c3-1 ceramic capacitor 10 f (25 v) murata 3216 grm31cb31e106k c3-2 ceramic capacitor 10 f (25 v) murata 3216 grm31cb31e106k c4-1 poscap 150 f (6.3 v) sanyo d case 6tpl150mu c4-3 ceramic capacitor 1000 pf (50 v) tdk 1608 c1608jb1h102k c5 ceramic capacitor 0.1 f (50 v) tdk 1608 c1608jb1h104k c6 ceramic capacitor 0.1 f (50 v) tdk 1608 c1608jb1h104k c7 ceramic capacitor 0.1 f (50 v) tdk 1608 c1608jb1h104k c8 ceramic capacitor 4.7 f (16 v) tdk 1608 c1608jb1c475k c12 ceramic capacitor 3300 pf (50 v) tdk 1608 c1608jb1h332k c13 ceramic capacitor 3300 pf (50 v) tdk 1608 c1608jb1h332k r1-1 resistor 1.6 k ? ssm 1608 rr0816p162d r1-2 resistor 27 k ? ssm 1608 rr0816p273d r2 resistor 68 k ? ssm 1608 rr0816p683d r3-1 resistor 0.047 k ? ssm 1608 rr0816p470d r3-2 resistor 56 k ? ssm 1608 rr0816p563d r4 resistor 36 k ? ssm 1608 rr0816p363d r5 resistor 110 k ? ssm 1608 rr0816p114d r6 resistor 120 k ? ssm 1608 rr0816p124d renesas : renesas electronics corporation sanyo : sanyo electric co., ltd nec tokin : nec tokin corporation tdk : tdk corporation murata : murata manufacturing co., ltd. ssm : susumu co.,ltd. 26 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? application note 1. setting operating conditions setting output volt ages the output voltage can be set by adjusting the setting output voltage resistor ratio. setting output voltage is calculated by the following formula. r1 + r2 2.8 10 -7 ? v outx v outx = r2 (0.6946 + 0.2667 ? i l (1 t off ) r on_sync ) + 2 v in v out v out (v in v outx ) ? v outx = esr ? i l, ? i l = l v in f osc , t off = v in f osc v outx : output setting voltage [v] v in : power supply voltage [v] ? v outx : output ripple voltage value [v] t off : off time [s] r on_sync : on resistance of low-side fet [ ] ? i l : ripple current peak-to-peak value of inductor [a] esr : series resistance element of output capacitor [ ] l : inductor value [h] f osc : switching frequency [hz] r1 v outx r2 vout x fb x the total resistor value (r1+r2) of the setting output resistor should be selected up to 100 k . x: each channel number 27 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e minimum power supply voltage the maximum on duty is limited by "the minimum off time (t offmin ) that an ic holds without fail as a fixed value" and "the on time (t on ) determined by the power voltage value and the output voltage setting value". the ratio between the output voltage and the power voltage must be less than the maximum on duty. the minimum power supply voltage th at is required to sustain the output voltage can be calculated by the following formula. (v out + i out_max (rdc + r on_main )) v out v in_min = v out ? (v out + i out_max (rdc + r on_sync )) t off_min f osc 1.2 v in_min : power supply voltage [v] v out : output setting voltage [v] i out_max : maximum load current value [a] r on_main : on resistance of high-side fet [ ? ] r on_sync : on resistance of low-side fet [ ? ] rdc : series resistance of inductor [ ? ] f osc : switching frequency setting value [hz] t off_min : minimum off time (maximum value) [s] (for the minimum off time, see ?on/off time [minimum off time ] ? in ? ? electrical characteristics?.) use the smaller switching frequency setting in order to make the voltage output possible with the lower power voltage. slope voltages it is necessary to sustain the slope voltage 15 mv or hi gher in order to obtain the stable switching cycle. the slope voltage can be calculated by the following formula. (v in ? v out ) v out r on_sync v slope = l v in f osc v slope : slope voltage [v] v in : power supply voltage [v] v out : output setting voltage [v] f osc : switching frequency [hz] r on_sync : on resistance of low-side fet [ ? ] l : inductor value [h] 28 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e setting soft-start time calculate the soft-start time by the following formula. t s = 7 10 5 c cs t s : soft-start time [s] (time until output reaches 100%) c cs : cs pin capacitor value [f] calculate the delay time until the soft-start activation by the following formula. t d = 43 c vb t d : vb voltage delay time (at v in = 12 v) [s] c vb : vb pin capacitor value [f] when activating the other in the state where a side channel has already been activated (uvlo release: vb output already), the delay time is hardly generated. t s1 t d t s2 en1 en2 v out1 v out2 29 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e setting switching frequency the switching frequency is set at the freq pin. as for the setting process, see the switching frequency control function table. setting over current limitation the over current limitation value can be set by adjusting the over current limitation setting resistor value connected to the ilim pin. calculate the resistor value by the following formula. i l r lim = 10 6 r on_sync (i lim ? 2 ) r lim : over current limitation value setting resistor [ ? ] i lim : over current limitation value [a] i l : ripple current peak-to-peak value of inductor [a] r on_sync : on resistance of low-side fet [ ? ] ilim r lim i out i lim 0 if the rate of inductor saturation current is small, th e inductor value decreases and the ripple current of inductor increase when the over-current flows. at that time there is a possibility that the limited output current increases or is not limited, because the bottom of inductor current is detected. it is necessary to use the inductor that has enough large rate of inducto r saturation current to prevent the overlap current. inductor current over current limitation value time i l 30 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e the over current limit value is affected by ilim pin s ource current and over current detection offset voltage in the ic except for the on resistance of the low-side fet and the inductor value. the variation of dropped over current limit value caused by ic characteristics is calculated by the following formula. 2 10 -7 r lim + 0.03 i lim = r on_sync i lim : the variation of dropped over current limit value [a] r lim : over current limitation value setting resistor [ ? ] r on_sync : on resistance of low-side fet [ ? ] i o 0 i lim i lim ? the over current detection value needs to set a su fficient margin against the maximum load current. inductor current dropped over current limit value due to ic's characteristics time over current limit value i lim 31 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e power dissipation and the thermal design ic's loss increases, if ic is used under the high power supply voltage, high switching frequency, high load and high temperature. the ic internal loss can be calculated by the following formula. p ic = v cc (i cc + q g_total1 f osc1 + q g_total2 f osc2 ) p ic : ic internal loss [w] v cc : power supply voltage (v in ) [v] i cc : power supply current [a] (2 ma max) q g_total1 : total quantity of charge for the high-side fet and the low-side fet of each ch1 [c] q g_total2 : total quantity of charge for the high-side fet and the low-side fet of each ch2 [c] f osc1 : ch1 switching frequency [hz] f osc2 : ch2 switching frequency [hz] calculate junction temperature (tj) by the following formula. tj = ta + ja p ic tj : junction temperature [c] (+ 125c max) ta : ambient temperature [c] ja : tssop-24p package thermal resistance (+ 78c /w) p ic : ic internal loss [w] handling of the pins when using a single channel although this device is a 2-channel dc/dc converter control ic, it is also able to be used as a 1-channel dc/dc converter by handling the pins of the unused channel as shown in the following diagram. note: x is the unused channel number. fbx voutx csx enx lxx ilimx drvhx bstx drvlx ?open? ?open? ?open? 32 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e 2. selecting parts selection of smoothing inductor the inductor value selects the value that the ripple curre nt peak-to-peak value of the inductor is 50% or less of the maximum load current as a rough standard. calculate the inductor value in this case by the following formula. v in ? v out v out l lor i out_max v in f osc l : inductor value [h] i out_max : maximum load current [a] lor : ripple current peak-to-peak value of inductor/maximum load current ratio (= 0.5) v in : power supply voltage [v] v out : output setting voltage [v] f osc : switching frequency [hz] it is necessary to calculate the maximum current valu e that flows to the inductor to judge whether the electric current that flows to the inductor is a rated value or less. calculate the maximum current value of the inductor by the following formula. i l il max i out_max + 2 il max : maximum current value of inductor [a] i out_max : maximum load current [a] i l : ripple current peak-to-peak value of inductor [a] l : inductor value [h] v in : power supply voltage [v] v out : output setting voltage [v] f osc : switching frequency [hz] i out_max il max 0 inductor current time i l 33 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e selection of switching fet if selecting the high-side fet so that the value of the high-side fet conduction loss and the high-side fet switching loss is same, the loss is effectively decreased. confirm that the high-side fet loss is within the rating value. p mainfet = p ron_main + p sw_main p mainfet : high-side fet loss [w] p ron_main : high-side fet conduction loss [w] p sw_main : high-side fet switching loss [w] high-side fet conduction loss v out p ron_main = i out_max 2 v in r on_main p ron_main : high-side fet conduction loss [w] i out_max : maximum load current [a] v in : power supply voltage [v] v out : output voltage [v] r on_main : on resistance of high-side fet [ ? ] the high-side fet switching loss can be calcu lated roughly by the following formula. p sw_main 1.56 v in f osc i out_max q sw p sw_main : switching loss [w] v in : power supply voltage [v] f osc : switching frequency [hz] i out_max : maximum load current [a] q sw : amount of high-side fet gate switch electric charge [c] mosfet has a tendency where the gate drive loss incr eases because the lower drive voltage product has the bigger amount of gate electric charge (q g ). normally, we recommend a 4 v drive product, however, the idle period at light load (both the high-side fet and th e low-side fet is off-period) gets longer and the gate drive voltage of the high-side fet may decrease, in the automatic pfm/pwm selection mode. the voltage drops most at no-load mode. at this time, confirm that the boost voltage (voltage between bst-lx pins) is a big enough value for the gate threshold value voltage of the high-side fet. if it is not enough, consider adding the boost diode, increasing the capacitor value of the boost capacitor or using a 2.5 v (or 1.8 v) drive product to the high-side fet. select the on resistance of low-side fet from the range below. 0.2 0.1 0.015 r on_sync i l , r on_sync i l , r on_sync i l (i lim ? 2 ) r on_sync : on resistance of low-side fet [ ? ] i l : ripple current peak-to-peak value of inductor [a] i lim : over current detection value [a] 34 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e if the formula above has been already satisfied and then a low on resistance fet as possible is used for the low-side fet, the loss is effectively decreased. especially, it works dramatically in the low on duty mode. the loss of the low-side fet can be calculated by the following formula. v out p syncfet = p ron_sync = i out_max 2 (1 ? v in ) r on_sync p syncfet : low-side fet loss [w] p ron_sync : low-side fet conduction loss [w] i out_max : maximum load current [a] v in : power supply voltage [v] v out : output voltage [v] r on_sync : on resistance of low-side fet [ ? ] turn-on and turn-off voltage of the low-side fet is generally small and the switching loss is small enough to ignore, so that is omitted here. especially, when turning on the high-side fet under the high power supply voltage condition, the rush-current might be generated by according to self-turn-on of the low-side fet. the parasitic capacitor value of the low-side fet needs to satisfy the following conditions. c rss v th_sync > c iss v in v th_sync : threshold voltage of low-side fet [v] c rss : parasitic feedback capacitance of low-side fet [f] c iss : parasitic input capacitance of low-side fet [f] v in : power supply voltage [v] also approaches of adding a capacitor close between the gate source pins of the low-side fet or adding resistor between the bst pin and the boost capacitor, and so on are effective as a countermeasure of the self-turn-on(adding resistor between the bst pin and th e boost capacitor is also effective to adjust turn-on time of the high-side fet). this device monitors the gate voltage of the switching fet and optimizes the dead time. if the dumping resistor is inserted among drvh, drvl and the switching fet gate to adjust turn-on and turn-off time of the switching fet, this function might malfunction. in this device, resistor should not be connected among the drvh pin, the drvl pin of ic and the switching fet gate, and should be connected by low impedance as possible. the gate drive power of the switching fet is supplied from ldo (vb) of ic inside. select switching fet so that the total amount of the switching fet electric charge for 2 channels (qg_total1, qg_total2) satisfies the following formula. i vb_max > q g_total1 f osc1 + q g_total2 f osc2 i vb_max : vb load current upper limit value (see the following graph) [a] q g_total1 : total quantity of charge for the high-side fet and the low-side fet of each ch1 [c] q g_total2 : total quantity of charge for the high-side fet and the low-side fet of each ch2 [c] f osc1 : ch1switching frequency [hz] f osc2 : ch2 switching frequency [hz] 35 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e 6 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 8 10121416182022242628 moreover, select the total quantity of the high-side fe t electric charge as a guide that does not exceed the total quantity of the high-side fet electric charge upper limit value shown below. 5 1015202530 35 30 25 20 15 10 5 0 freq=gnd:ch1 freq=gnd:ch2 freq=open:ch1 freq=open:ch2 freq=vb:ch1 freq=vb:ch2 whether the mean current value that flows to switching fet is a rated value or less of switching fet is judged. each rating value for the switching fet can be calculated roughly by the following formula. i d_main > i out_max d i d_sync > i out_max (1 ? d) i d_main : high-side fet drain current [a] i d_sync : low-side fet drain current [a] i out_max : maximum load current [a] d : on-duty v dss > v in v dss : voltage between the high-side fet drain and source and the low-side fet drain and source [v] v in : power supply voltage [v] vb load current upper limit value [a] v in [v] power supply voltage v in [v] the total quantity upper limit of electric charge of the high-side fet q g_max [nc] from the top line 36 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e selection of fly-back diode this device is improved by adding the fly-back diode when the conversion efficiency improvement or the suppression of the low-side fet fever is desired, a lthough those are unnecessary to execute normally. the effect is achieved in the condition where the switching frequency is high or output voltage is lower. select schottky barrier diode (sbd) that the forward current is as small as possible. in this dc/dc control ic, the period for the electric current flow into fly-back diode is limited to dead time period because the synchronous rectification system is adopted. (as for the dead time, see ?output block? in ?electrical characteristics?). each rating for the fly-back diode can be calculated by the following formula. i d i out_max f osc (t d1 + t d2 ) i d : forward current rating of sbd [a] i out_max : maximum load current [a] f osc : switching frequency [hz] t d1 , t d2 : dead time [s] i l i fsm i out_max + 2 i fsm : peak forward surge current ratings of sbd [a] i out_max : maximum load current [a] i l : ripple current peak-to-peak value of inductor [a] v r_fly > v in v r_fly : reverse voltage of fly-back diode direct current [v] v in : power supply voltage [v] 37 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e selection of input capacitor select the input capacitor whose esr is as small as possible. the ceramic capacitor is an ideal. use the tantalum capacitor and the polymer capacitor of the low esr when a mass capacitor is needed as the ceramic capacitor can not support. the ripple voltage is generated in the power supply voltage by the switching operation of dc/dc. calculate the lower bound of input capacitor according to an allowa ble ripple voltage. calculate the ripple voltage of the power supply from the following formula. i out_max v out i l v in = c in v in f osc + esr (i out_max + 2 ) v in : power supply ripple voltage peak-to-peak value [v] i out_max : maximum load current value [a] c in : input capacitor value [f] v in : power supply voltage [v] v out : output setting voltage [v] f osc : switching frequency [hz] esr : series resistance component of input capacitor [ ? ] i l : ripple current peak-to-peak value of inductor [a] capacitor has frequency characteristic, the temperature characteristic, and the bias voltage characteristic, etc. the effective capacitor value might become extremely small depending on the use conditions. note the effective capacitor value in the use conditions. calculate ratings of the input capacitor by the following formula: v cin > v in v cin : withstand voltage of the input capacitor [v] v in : power supply voltage [v] v out (v in ? v out ) irms i omax v in irms : allowable ripple current of input capacitor (effective value) [a] i omax : maximum load current value [a] v in : power supply voltage [v] v out : output setting voltage [v] 38 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e selection of output capacitor a certain level of esr is required for stable operati on of this ic. use a tantalum capacitor or polymer capacitor as the output capacitor. if using a ceramic capac itor with low esr, a resistor should be connected in series with it to increase esr equivalently. calculate the output capacitor value by the following formula as a guide. 1 c out 4 f osc esr c out : output capacitor value [f] f osc : switching frequency [hz] esr : series resistance of output capacitor [ ? ] moreover, the output capacitor values are also derived from the allowable amount of overshoot and undershoot. the following formula is represented as the worst condition in which the shift time for a sudden load change is 0s. the output capacitor value allow a smaller amount than the value calculated by the following formula when a longer shift time. i out 2 l c out 2 v out v out_over ? overshoot condition i out 2 l (v out + v in f osc t off_min ) c out 2 v out v out_under (v in ? v out ? v in f osc t off_min ) ? undershoot condition c out : output capacitor value [f] v out_over : allowable amount of output voltage overshoot [v] v out_under : allowable amount of output voltage undershoot [v] i out : current difference in sudden load change [a] l : inductor value [h] v in : power supply voltage [v] v out : output setting voltage [v] f osc : switching frequency [hz] t off_min : minimum off time when changing to no load suddenly, the output volta ge is overshoot, however, the current sink is not executed in the mode other than pwm fix. as a result, the decrement of the output voltage might take a long time. this sometimes results in the stop mode because of the over voltage detection. in the mode other than pwm fix, select the capacitor value so that the overshoot value is set to the over voltage detection voltage value or less (115% of the output setting voltage or less). the capacitor has frequency, operating temperature, and bi as voltage characteristics, etc. therefore, it must be noted that its effective capacitor value may be significantly smaller, depending on the use conditions. 39 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e calculate each rating of the output capacitor by the following formula: v cout > v out v cout : withstand voltage of the output capacitor [v] v out : output voltage [v] i l i rms 2 3 i rms : allowable ripple current of output capacitor (effective value) [a] i l : ripple current peak-to-peak value of inductor [a] when connecting resistance in series configuration while a ceramic capacitor is in use, the resistor rating is calculated by the following formula. esr i l 2 p esr > 12 p esr : power dissipation of resistor [w] esr : resistor value [ ? ] i l : ripple current peak-to-peak value of inductor [a] 40 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e selection of bootstrap capacitor to drive the gate of high-side fet, the bootstrap capacitor must have enough stored charge. 0.1 f is assumed to be standard, however, it is necessary to adjust it when the high-side fet q g is big. consider the capacitor value calculated by the following formula as the lowest value for the bootstrap capacitor and select a thing any more. c bst 10 q g c bst : bootstrap capacitor value [f] q g : total quantity of charge for the high-side fet gate [c] calculate ratings of the bootstrap capacitor by the following formula: v cbst > v b v cbst : withstand voltage of the bootstrap capacitor [v] v b : vb voltage [v] vb pin capacitor 4.7 f is assumed to be a standard, and when q g of switching fet used is large, it is necessary to adjust it. to suppress the ripple voltage by the switching fet gate drive, consider the capacitor value calculated by the following formula as the lowest value for vb capacitor and select a thing any more. c vb 50 q g c vb : vb pin capacitor value [f] q g : total amount of gate charge of high-side fet and low-side switching fet for 2ch [c] calculate ratings of the vb pin capacitor by the following formula: v cvb > v b v cvb : withstand voltage of the vb pin capacitor [v] v b : vb voltage [v] 41 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e layout consider the points listed below and do the layout design. y provide the ground plane as much as possible on the ic mounted face. connect bypass capacitor connected with the vcc and vb pins, and gnd pin of the switching system parts with switching system gnd (pgnd). connect other gnd connection pins wi th control system gnd (agnd), and separate each gnd, and try not to pass the heavy current path through the control system gnd (agnd) as much as possible. in that case, connect control system gnd (agnd) and switching system gnd (pgnd) at the single point of gnd (pgnd) directly below ic. switching system parts are input capacitor (c in ), switching fet, fly-back diode (sbd), inductor (l) and output capacitor (c out ). y connect the switching system parts as much as possible on the surface. avoid the connection through the through-hole as much as possible. y as for gnd pins of the switching system parts, provide the through hole at the proximal place, and connect it with gnd of internal layer. y pay the most attention to the loop composed of input capacitor (c in ), switching fet, and fly-back diode (sbd). consider parts are disposed mutually to be n ear for making the current loop as small as possible. y place the bootstrap capacitor (c BST1 , c bst2 ) proximal to bstx and lxx pins of ic as much as possible. y connect the line to the lx pin proximal to the drain pin of low-side fet. also large electric current flows momentary in this net. wire the line of width of about 0.8 mm as standard, and as short as possible. y large electric current flows momentary in the net of drvhx and drvlx pins connected with the gate of switching fet. wire the linewidth of about 0.8 mm to be a standard, as short as possible. take special care about the line of the drvlx pin, and wire the line as short as possible. y by-pass capacitor (c vcc , c vb ) connected with vcc, and vb should be placed close to the pin as much as possible. also connect the gnd pin of the bypass capacitor with gnd of internal layer in the proximal through-hole. y pull the feedback line to be connected to the voutx pin of the ic separately from near the output capacitor pin, whenever possible. consider the line connected with voutx and fbx pins to keep away from a switching system parts as much as possible because it is sensitive to the noise. also, place the output voltage setting resistor connected to this line near ic, and try to shorten the line to the fbx pin. in addition, for the internal layer right under the component mounting place, provide the control system gnd (agnd) of few ripple and few spike noises, or provide the ground plane of the power supply as much as possible. consider that the discharge current momentary flows into the voutx pin (about 200 ma at vout = 5 v) when the dc/dc operation stops, and then sustain the width for the feedback line. there is leaked magnetic flux around the inductor or backside of place equipped with inductor. line and parts sensitive to noise should be considered to be placed away from the inductor (or backside of place equipped with inductor). 1pin agnd agnd pgnd pgnd c bst2 c vcc c vb c BST1 sbd(option) pgnd vin c in ll c in sbd (option) c out c out v out1 v out2 layout example of ic peripheral layout example of switching system parts through-hole connect agnd and pgnd right under ic surface internal layer output voltage setting resistor layout low-side fet to the lx1 pin low-side fet to the lx2 pin output voltage v out2 feedback output voltage v out1 feedback high-side fet high-side fet 42 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? reference data conversion efficiency vs.load current conversion efficiency vs.load current conversion efficiency (%) 100 90 80 70 60 50 40 30 20 10 0 0.001 0.01 0.1 1 10 pfm/pwm pa f pwm v in = 12 v v out1 = 1.0 v freq = open ta = +25c conversion efficiency (%) 100 90 80 70 60 50 40 30 20 10 0 0.001 0.01 0.1 1 10 pfm/pwm pa f v in = 12 v v out2 = 1.8 v freq = open ta = +25c pwm load current i out1 (a) load current i out2 (a) switching frequency vs. load current switching frequency vs. load current switching frequency fosc1 (khz) 1000 100 10 1 0.001 0.01 0.1 1 1 0 pfm/pwm pa f v in = 12 v v out1 = 1.0 v freq = open ta = + 2 5 c pwm switching frequency fosc2 (khz) 1000 100 10 1 0.001 0.01 0.1 1 1 0 pfm/pwm pa f v in = 12 v v out2 = 1.8 v freq = open ta = +25c pwm load current i out1 (a) load current i out2 ( a) output voltage vs. load current output voltage vs. load current output voltage v out1 (v) 1.05 1.04 1.03 1.02 1.01 1.00 0.99 0.98 0.97 0.96 0.95 0.001 0.01 0.1 1 10 pfm/pwm pa f v in = 12 v v out1 = 1.0 v freq = open ta = +25c pwm output voltage v out2 (v) 1.90 1.88 1.86 1.84 1.82 1.80 1.78 1.76 1.74 1.72 1.70 0.001 0.01 0.1 1 1 0 pfm/pwm pa f v in = 12 v v out2 = 1.8 v freq = open ta = + 2 5 c pwm load current i out1 (a) load current i out2 (a) 43 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ripple waveform v in =12 v, v out1 =1.0 v, i out1 =0 a, mode=gnd, freq=open, ta=+25c v out1 20 mv/div 100 ms/div v in =12 v, v out2 =1.8 v, i out2 =0 a, mode=gnd, freq=open, ta=+25c v out2 20 mv/div 20 ms/div v in =12 v, v out1 =1.0 v, i out1 =7 a, mode=gnd, freq=open, ta=+25c v out1 20 mv/div 2 s/div v in =12 v, v out2 =1.8 v, i out2 =7 a, mode=gnd, freq=open, ta=+25c v out2 20 mv/div 2 s/div load sudden change waveform v in =12 v, v out1 =1.0 v, i out1 =0 a 4 a, mode=gnd, freq=open, ta=+25c v out1 50 mv/div i out1 2 a/div 10 s/div 4 a 0 a v in =12 v, v out2 =1.8 v, i out2 =0 a 4 a, mode=gnd, freq=open, ta=+25c v out2 50 mv/div i out2 2 a/div 10 s/div 4 a 0 a 44 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e en startup and shutdown waveform v in =12 v, v out1 =1.0 v, i out1 =7 a (0.14 ? ), mode=gnd, freq=open, ta=+25c en1 10 v/div v out1 500 mv/div lx1 10 v/div 500 s/div v in =12v, v out2 =1.8 v, i out2 =7 a (0.26 ? ), mode=gnd, freq=open, ta=+25c en1 10v/div v out1 500 mv/div lx1 10v/div 500 s/div output over current waveform v in =12 v, v out1 =1.0 v,mode=vb,freq=open, ta=+25c i out1 5 a/div v out1 500 mv/div lx1 10 v/div 100 s/div normal operation over current limitation under voltage protection 45 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? usage precaution 1. do not configure the ic over the maximum ratings. if the ic is used over the maximum ratings, the lsi may be permanently damaged. it is preferable for the device to normally operate within the recommended usage conditions. usage outside of these conditions can have an adverse effect on the reliability of the lsi. 2. use the device within the recommended operating conditions. the recommended values guarantee the normal lsi operation under the recommended operating conditions. the electrical ratings are guaranteed when the device is used within the recommended operating conditions and under the conditions stated for each item. 3. printed circuit board ground lines should be se t up with consideration for common impedance. 4. take appropriate measures against static electricity. y containers for semiconductor materials should have anti-static protection or be made of conductive material. y after mounting, printed circuit boards should be stor ed and shipped in conductive bags or containers. y work platforms, tools, and instru ments should be properly grounded. y working personnel should be grounded with resistance of 250 k ? to 1 m? in serial body and ground. 5. do not apply negative voltages. the use of negative voltages below 0.3 v may make the parasitic transistor activated to the lsi, and can cause malfunctions. 46 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? ordering information part number package remarks mb39a214apft 24-pin plastic tssop (fpt-24p-m09) ? ev board ordering information ev board number ev board version no. remarks mb39a214a-evb-01 mb39a214a-evb -01 rev. 1.0 tssop-24 47 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? rohs compliance information of lead (pb) free version the lsi products of fujitsu semiconductor with ?e 1? are compliant with rohs directive, and has observed the standard of lead, cad mium, mercury, hexavalent chromium , polybrominated biphenyls (pbb), and polybrominated diphenyl ethers (pbde). a product whose part number has trailing characters ?e1? is rohs compliant. ? marking format (lead free version) xxxx 39a214a xxx e1 index lead-free version 48 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? labeling sample (lead free version) 2006/03/01 assembled in japan g qc pass (3n) 1mb123456p-789-ge1 1000 (3n)2 1561190005 107210 1,000 pcs 0605 - z01a 1000 1/1 1561190005 mb123456p - 789 - ge1 mb123456p - 789 - ge1 mb123456p - 789 - ge1 pb lead-free mark jeita logo jedec logo the part number of a lead-free product has the trailing characters "e1". "assembled in china" is printed on the label of a product assembled in china. 49 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? mb39a214apft recommended conditions of moisture sensitivity level [fujitsu semiconductor recommended mounting conditions] item condition mounting method ir (infrared reflow), warm air reflow mounting times 2 times before opening please use it within two years after manufacture. from opening to the 2nd reflow less than 8 days storage period when the storage period after opening was exceeded please process within 8 days after baking (125c 3c, 24h+ 2h/ 0h) . baking can be performed up to two times. storage conditions 5c to 30c, 70% rh or less (the lowest possible humidity) [mounting conditions] (1) ir (infrared reflow) 260c (e) (d') (d) 245c 170 c 190 c rt (b) (a) (c) to main heating "m" rank : 250c max (a) temperature increase gradi ent : average 1c/s to 4c /s (b) preliminary heating : temperature 170c to 190c, 60 s to 180 s (c) temperature increase gradient : average 1c /s to 4c /s (d) peak temperature : temperature 250c max; 245c or more, 10 s or less (d') main heating : temperature 230c or more, 40 s or less or temperature 225c or more, 60 s or less or temperature 220c or more, 80 s or less (e) cooling : natural cooling or forced cooling note: temperature : the top of the package bod 50 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e (2) manual soldering (partial heating method) item condition before opening within two years after manufacture storage period between opening and mounting within two years after manufacture (no need to control moisture during the storage period because of the partial heating method.) storage conditions 5c to 30c, 70% rh or less (the lowest possible humidity) mounting conditions temperature at the tip of a soldering iron: 400c max time: five seconds or below per pin* *: make sure that the tip of a soldering iron does not come in contact with the package body. 51 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? package dimensions 24-pin plastic tssop lead pitch 0.50 mm package width package length 4.40 mm 6.50 mm lead shape gullwing sealing method pl asti c mol d mounting height 1.20 mm max weight 0.08 g 24-pin plastic tssop (fpt-24p-m09) (fpt-24p-m09) c 2007-2010 fujits u semiconductor limited f24032s-c-2-5 6.50 0.10 (.256. 004) # 4.40 0.10 6.40 0.20 (.252. 008) (.173. 004) # 0.10 0.05 (mounting height) 0.10(.004) 0.50(.020) 1 12 24 13 "a" (stand off) 0.145 0.045 (.0057. 0018) m 0.13(.005) details of "a" part 0~8 (.024. 006) 0.60 0.15 index (.004. 002) btm e-mark 1.10 +0.10 +.004 ?0.15 ?.006 .043 0.20 +0.07 +.003 ?0.02 ?.001 .008 dimensions in mm (inches). note: the values in parentheses are reference values. note 1) pins width and pins thickness include plating thickness. note 2) pins width do not incl ude tie bar cutting remainder. note 3) #: these dimensions do not include resin protrusion. please check the latest package dimension at the following url. http://edevice.fujitsu.com/package/en-search/ 52 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e ? contents page ? description................................................................................................................................. 1 ? features ....................................................................................................................................... 1 ? applications............................................................................................................................... 1 ? pin assignment................................................................................................................. ......... 2 ? pin descriptions ............................................................................................................... ........ 3 ? block diagram .................................................................................................................. ....... 4 ? absolute maximum ratings .............................................................................................. 5 ? recommended operating conditions........................................................................... 6 ? electrical characteristics ............................................................................................. 7 ? typical characteristics................................................................................................... 10 ? function..................................................................................................................................... 13 ? i/o pin equivalent circuit diagram............................................................................. 22 ? example application circuit .......................................................................................... 24 ? part list...................................................................................................................... ................ 25 ? application note ............................................................................................................... .... 26 ? reference data................................................................................................................. ...... 42 ? usage precaution ................................................................................................................. 45 ? ordering information........................................................................................................ 46 ? ev board ordering information .................................................................................. 46 ? rohs compliance information of lead (pb) free version ................................ 47 ? marking format (lead free version).................................................................................... 47 ? labeling sample (lead free version) .................................................................................... 48 ? mb39a214apft recommended conditions of moisture se nsitivity level 49 ? package dimensions............................................................................................................. 51 ? contents .................................................................................................................................... 52 53 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e 54 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e 55 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e 56 mb39a214a limitation : development tool vendor use only fujitsu semiconductor confidential ds405-00007-1v0-e fujitsu semiconductor limited nomura fudosan shin-yokohama bldg. 10-23, shin-yokohama 2-chome, kohoku-ku yokohama kanagawa 222-0033, japan tel: +81-45-415-5858 http://jp.fujitsu.com/fsl/en/ for further information please contact: north and south america fujitsu semiconductor america, inc. 1250 e. arques avenue, m/s 333 sunnyvale, ca 94085-5401, u.s.a. tel: +1-408-737-5600 fax: +1-408-737-5999 http://us.fujitsu.com/micro/ europe fujitsu semiconductor europe gmbh pittlerstrasse 47, 63225 langen, germany tel: +49-6103-690-0 fax: +49-6103-690-122 http://emea.fujitsu.com/semiconductor/ korea fujitsu semiconductor korea ltd. 902 kosmo tower building, 1002 daechi-dong, gangnam-gu, seoul 135-280, republic of korea tel: +82-2-3484-7100 fax: +82-2-3484-7111 http://kr.fujitsu.com/fsk/ asia pacific fujitsu semiconductor asia pte. ltd. 151 lorong chuan, #05-08 new tech park 556741 singapore tel : +65-6281-0770 fax : +65-6281-0220 http://sg.fujitsu.com/semiconductor/ fujitsu semiconductor shanghai co., ltd. 30f, kerry parkside, 1155 fang dian road, pudong district, shanghai 201204, china tel : +86-21-6146-3688 fax : +86-21-6146-3660 http://cn.fujitsu.com/fss/ fujitsu semiconductor pacific asia ltd. 10/f., world commerce centre, 11 canton road, tsimshatsui, kowloon, hong kong tel : +852-2377-0226 fax : +852-2376-3269 http://cn.fujitsu.com/fsp/ specifications are subject to change without notice. for further information please contact each office. all rights reserved. the contents of this document are subject to change without notice. customers are advised to consult with sales representatives before ordering. the information, such as descriptions of function and applicat ion circuit examples, in this document are presented solely for the purpose of reference to show examples of operati ons and uses of fujitsu semiconductor device; fujitsu semiconductor does not warrant proper operation of the devi ce with respect to use based on such information. when you develop equipment incorporating the device based on such information, you must assume any responsibility arising out of such use of the information. fujitsu semiconductor assumes no liability for any damages whatsoever arising out of the use of the information. any information in this document, including descriptions of function and schematic diagrams, shall not be construed as license of the use or exercise of any intellectual property right, such as patent right or copyright, or any other right of fujitsu semiconductor or any third party or does fujitsu semiconductor warrant non-infringement of any third-party's intellectual property right or other right by using such information. fujitsu semiconductor assumes no liability for any infringement of the intellectual property rights or other rights of third parties which would result from the use of information contained herein. the products described in this document are designed, developed and manufactured as contemplated for general use, including without limitation, ordinary industrial use, genera l office use, personal use, and household use, but are not designed, developed and manufactured as contemplated (1) for use accompanying fatal risks or dangers that, unless extremely high safety is secured, could have a serious effect to the public, and could lead directly to death, personal injury, severe physical damage or other loss (i.e., nuclear reaction contro l in nuclear facility, aircraft flight control, air traffic control, mass transport control, medical life support system, missile launch control in weapon system), or (2) for use requiring extremely high reliability (i.e., subm ersible repeater and artificial satellite). please note that fujitsu semiconductor will not be liable against you and/or any third party for any claims or damages arising in connection with above-mentioned uses of the products. any semiconductor devices have an inherent chance of failure. you must protect against injury, damage or loss from such failures by incorporating safety design measures into your f acility and equipment such as redundancy, fire protection, and prevention of over-current levels and other abnormal operating conditions. exportation/release of any products described in this document may require necessary procedures in accordance with the regulations of the foreign exchange and foreign trade control law of japan and/or us export control laws. the company names and brand names herein are the trademarks or registered trademarks of their respective owners. edited: sales promotion department |
Price & Availability of BST1
 |
|
|
|
|
All Rights Reserved © IC-ON-LINE 2003 - 2022 |
| [Add Bookmark] [Contact Us] [Link exchange] [Privacy policy] |
|
Mirror Sites : [www.datasheet.hk]
[www.maxim4u.com] [www.ic-on-line.cn]
[www.ic-on-line.com] [www.ic-on-line.net]
[www.alldatasheet.com.cn]
[www.gdcy.com]
[www.gdcy.net] |