MIC45116 evaluation board 20v/6a/dc - to - dc power module general description micrel?s MIC45116 is a synchronous step - down regulator module, featuring a unique adaptive on - time control architecture. the singular module package in cludes a dc - to - dc controller, power mosfets, bootstrap diode, bootstrap capacitor, and an inductor; simplifying the design and layout process for the end user. this highly integrated solution expedites system design and improves product time - to - market. the i nte rnal mosfets and inductor have been optimized to achieve high efficiency at a low output voltage. the fully optimized design can deliver up to a 6a current under a wide input voltage range of 4. 7 5v to 20v, without an additional cooling requirement . the mic 45116 - 1 uses micrel?s hyperlight load ? (hll) . MIC45116 - 2 uses micrel?s hyper speed control? architecture which enables ultra - fast load transient response and allow s for a re duction of output capacitance. the MIC45116 offers 1% output accuracy that can be a djusted from 0.8v up to 85 % of the input voltage with two external resistors. n ote the output capacitor cb is only rated to 6.3v. the basic parameters of th is evaluation board include a 4. 7 5v to 20v input, a 0.8v to 5v at 6a output . datasheets and support documentation are available on micrel?s web site at : www.micrel.com . requirements the MIC45116 - 1 and MIC45116 - 2 evaluation board?s minimum requirement is one power supply with at least 6 a current capability. no external linear regulator is required to power the internal biasing of the ic because the MIC45116 has an internal pvdd ldo. in the applications with vin < +5.5v, pv dd should be tied to vin to bypass the internal linear regulator. the output load can either be a passive or an active load. precautions the MIC45116 evaluation board does not have reverse polarity protection. applying a negative voltage to the vin and gnd terminals may damage the device. the maximum vin of the board is rated at 20v. exceeding 30v on the vin could damage the device. the voltage rating of the output capacitor is 6.3v. the output capacitor should be replaced with higher voltage rated one to set the output voltage above 5v . getting started 1. vin supply connec t a supply to the vin (tp6) and gnd (tp7) terminals, paying careful attention to the polarity and the supply range (4. 75 v < vin < 20v). monitor iin with a current meter and monitor input voltage at vin and gnd terminals with a voltmeter. do not apply power until step 4. 2. connect load and monitor output connect a load to the vout (tp8) and gnd (tp9) terminals. the load can be either a passive (resistive) or an active (as in an electronic load) type. a current meter may be placed between the vout terminal and load to monitor the outp ut current. ensure the output voltage is monitored at the vout terminal. 3. enable input the en pin has an on board 100k? pull - up resistor (r4) to vin, which allows the output to be turned on when pvdd exceeds its uvlo threshold. an en connector (tp3) is provided on the evaluation board for users to easily access the enable feature. applying an external logic signal on the en pin to pull it low or using a jumper to short the en pin to gnd will shut off the output of the MIC45116 evaluation board. 4. turn power turn on the vin supply and verify that the output voltage is regulated to 1.8 v. 5. loop measurement control loop frequency response can be measured by injecting ac sweep signal and measuring voltage across test points a and b. r3 should change to a small resistor va lue in the range of 10 ? to 20 ? for the loop measurement. ordering information part number description MIC45116 - 1ymp ev MIC45116 - 1 evaluation board MIC45116 - 2ymp ev MIC45116 - 2 evaluation board hyper lightload is a registered trademark of micrel, inc. hyper speed control is a trademark of micrel , inc. micrel inc. ? 2180 fortune drive ? san jose, ca 95131 ? usa ? tel +1 (408) 944- 0800 ? fax + 1 (408) 474 - 1000 ? http://www.micrel.com march 1 2 , 2015 revision 1.0
micrel, inc. MIC45116 evaluation board features feedback resistors the output voltage on the MIC45116 evaluation board, which is preset to 1.8v, is determined by the feedback divider, as illustrated in equation 1 : ? ? ? ? ? ? ? ? + = bottom ref out r r51 1 v v eq. 1 where v ref = 0.8v, and r bottom is the lower feedback resistor. leaving the r bottom open by removing all jumpers on the feedback headers gives a 0.8v output voltage. all other voltages not listed above can be set by modifying r bottom value according to equation 2 : ref out ref bottom v v v r51 r ? = table 1 . typical values of some components v out vin r51 (top feedback resistor) r (bottom feedback resistor) c12 (c ff ) c out 1.0v 5v to 20v n
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1.0nf 100f/6.3v 1.2v 5v to 20v n
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1.0nf 100f/6.3v 1.5v 5v to 20v n
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1.0nf 100f/6.3v 1.8v 5v to 20v n
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1.0nf 100f/6.3v 2.5v 5v to 20v n
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1.0nf 100f/6.3v 3.3v 5v to 20v n
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1.0nf 100f/6.3v 5v 7v to 20v n
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1.0nf 100f/6.3v march 1 2 , 2015 2 revision 1.0
micrel, inc. MIC45116 evaluation board sw node a t est pad (sw) is placed close to the module for monitoring the switching waveform . it is one of the most critical waveforms for the converter. current limit the MIC45116 uses the r ds(on) of the low - side mosfet and external resistor connected from the ilim pin to the sw node to decide the current limit. vin sw ilim pgnd c5 r26 c16 pvin MIC45116 figure 1 . MIC45116 current - limiting circuit in each switching cycle of the mic4 5116, the inductor current is sensed by monitoring the low - side mosfet in the off period. the sensed voltage ( v (ilim) ) is compared with the power ground (pgnd) after a blanking time of 150ns. in this way the drop voltage over the r26 resistor (v cl ) is comp ared with the drop over the bottom fet generating the short current limit. the small capacitor (c16) connected from ilim pin to pgnd filters the switching node ringing during the off - time allowing a better short - limit measurement. the time constant created by r26 and c16 should be much less than the minimum off time. the v cl drop allows programming of short limit through the value of the resistor (r26) if the absolute value of the voltage drop on the bottom fet is greater than v cl . in that case the v (ilim) is lower than pgnd and a short circuit event is triggered. a hiccup cycle to treat the short event is generated. the hiccup sequence including the soft - start reduces the stress on the switching fets and protects the load and supply for severe short condit ions. the short - circuit current limit can be programmed by using equation 3 : ( ) (i r26 + ? = typically v cl = current - limit threshold (typical absolute value is 14mv per electrical characteristics in the MIC45116 data sheet) i cl = current - limit source current (typical value is 80a, per electrical characteristics in the MIC45116 data sheet). ? , l(pp) = inductor current peak - to - peak, since the inductor is integrated, use equation 4 to calculate the inductor ripple current. the peak - to - peak inductor current ripple is: l f v ) v (v v i sw in(max) out in(max) out l(pp) ? = ? and c16 = 15pf, the typical output current limit is about 8.2a. march 1 2 , 2015 3 revision 1.0
micrel, inc. MIC45116 evaluation board MIC45116 evaluation board schematic figure 2 . schematic of MIC45116 evaluation board march 1 2 , 2015 4 revision 1.0
micrel, inc. MIC45116 evaluation board bill of materials item part number manufacturer description qty . c 4 b41125a 533 7m tdk ( 1 ) 330f/2 5v, ale capacitor (optional) 1 c2, c3, c 7 , c 8 , c 9 , c11, c17 open c1 c3216x5r1e106m085ac tdk 10uf/25 v, 1206, x5r, 2 0%, mlcc 1 c5, c10 , c13, c14, c15 grm188r71h104ka93d murata ( 2 ) 0.1f/50v, x7r, 0603, 10%, mlcc 5 c6 c3216x5r0j107m160ab tdk 100f/6.3v, x5r, 1206, 20%, mlcc 1 c12 c1608c0g1h102j080aa tdk 1.0 nf/50v, np0, 0603, 5%, mlcc 1 c16 grm1885c1h150ja01d murata 15pf/50v, np0, 0603, 5%, mlcc 1 con1, con2, con3, con4 8191 keystone ( 3 ) 15a, 4 - prong through- hole screw terminal 4 j1 m50 - 3500742 harwin ( 4 ) header 2 x7 1 j2, j3, tp3 ? tp5 90120 - 0122 molex ( 5 ) header 2 5 r4 crcw0603100k0fkea vishay dale ( 6 ) n
, 1%, 1/10w, 0603, thick film 1 r21, r1 open r55 crcw060340k2fkea vishay dale 40.2 n
, 1%, 1/10w, 0603, thick film 1 r31, r50 crcw06020k0fkea vishay dale 20 n
, 1%, 1/10w, 0603, thick film 2 r32 crcw060311k5fkea vishay dale n
: 7 k l f n ) l o p 1 r49 crcw06038k06fkea vishay dale n
1%, 1/10w, 0603, thick film 1 r52 crcw06034k75fkea vishay dale n
: 7 k l f n ) l o p 1 r53 crcw06033k24fkea vishay dale n
, 1%, 1/10w, 0603, thick film 1 r54 crcw06031k91fkea vishay dale n
1%, 1/10w, 0603, thick film 1 r2 crcw060349k9fkea vishay dale n
: 7 k l f n ) l o p 1 r51 crcw060310k0fkea vishay dale n
, 1%, 1/10w, 0603, thick film 1 r26 crcw06031k 62 fkea vishay dale n
: 7 k l f n ) l o p 1 r3, r12 rcg06030000z0ea vishay dale 0 ? resistor, 1%, 1/10w, 0603, thick film 2 tp6 ? tp9, a, b 1502- 2 keystone single - end, through- hole terminal 6 u1 mic45 116 - 1 ym p micrel, inc. ( 7 ) 20v /6a dc -to - dc power module 1 MIC45116 - 2ymp notes: 1. tdk: www.tdk.com . 2. murata: www.murata.com . 3. keystone: www.keyelco.com . 4. harwin: http://www.harwin.com 5. molex: www.molex.com . 6. vishay - dale: www.vishay.com . 7. micrel: www.micrel.com . march 1 2 , 2015 5 revision 1.0
micrel, inc. MIC45116 evaluation board pcb layout recommendations MIC45116 evaluation board top layer MIC45116 evaluation board copper layer 2 march 1 2 , 2015 6 revision 1.0
micrel, inc. MIC45116 evaluation board pcb layout recommendations (continued) MIC45116 evaluation board copper layer 3 MIC45116 evaluation board bottom layer march 1 2 , 2015 7 revision 1.0
micrel, inc. MIC45116 evaluation board micrel, inc. 2180 fortune drive san jose, ca 95131 usa tel +1 (408) 944 - 0800 fax +1 (408) 474- 1000 web http://www.micrel.com micrel, inc. is a leading global manufacturer of ic s olutions for the worldwide high - pe rformance linear and power, lan, and timing & communications markets. the company?s products include advanced mixed - signal, analog & power semiconductors; high - performance communication, clock management, mems - based clock oscillators & crystal - less clock generators, ethernet switch es, and physical layer transceiver ics. company customers include leading manufacturers of enterprise, consumer, industrial, mobile, telecommunications, automotive, and computer products. corporation headquarters and state - of- the - art wafer fabrication facilities are located in san jose, ca, with regional sales and support offices and advanced technology design centers situated through out the americas, europe , and asia. additionally , the company maintains an extensive network of distributors and reps worldwide. micrel makes no representations or warranties with respect to the accuracy or completeness of the inf ormation furnished in th is data sheet. this information is not intended as a warranty and micrel does not assume responsibility for its use. micrel reserves the right to change circuitry, specifications and descriptions at any time without notice. no license, whether express, im plied, arising by estoppel or otherwise, to any intellectual property rights is granted by this document . e xcept as provided in micrel?s terms and conditions of sale for such products, micrel assumes no liability whatsoever, and micrel disclaims any expres s or implied warranty relating to the sale and/or use of micrel products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright , or other intellectual property right. micre l products are not designed or authorized for use as components in life support appliances, devices or systems where malfunct ion of a product can reasonably be expected to result in personal injury. life support devices or systems are devices or systems th at (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. a purchaser?s use or sale of micrel products for use in life suppo rt appliances, devices or systems is a purchaser?s own risk and purchaser agrees to fully indemnify micrel for any damages resulting from such use or sale. ? 2015 micrel, incorporated. march 1 2 , 2015 8 revision 1.0
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