ap1513 pwm control 2a step-down converter ap1513 rev. 2 1 of 8 august 2007 www.diodes.com ? diodes incorporated ? input voltage: 3.6v to 18v ? output voltage: 0.8v to v cc ? duty ratio: 0% to 100% pwm control ? oscillation frequency: 300khz typ. ? soft-start, current limit, enable function ? thermal shutdown function ? built-in internal sw p-channel mos ? sop-8l: available in ?green? molding compound ? lead free finish/rohs compliant (note 1) ap1513 consists of step-down switching regulator with pwm control. these devices include a reference voltage source, oscillation circuit, error amplifier, and internal pmos. ap1513 provides low-ripple power, high efficiency, and excellent transient characteristics. the pwm control circuit is able to vary the duty ratio linearly from 0 up to 100%. this converter also contains an error amplifier circuit as well as a soft-start circuit that prevents overshoot at startup. an enable function, an over current protect function and a short circuit protect function are built inside, and when ocp or scp happens, the operation frequency will be reduced from 300khz to 30khz. also, an internal compensation block is built in to minimum external component count. with the addition of an internal p-channel power mos, a coil, capacitors, and a diode connected externally, these ics can function as step-down switching regulators. they serve as ideal power supply units for portable devices when coupled with the sop?8l mini-package, providing such outstanding features as low current consumption. since this converter can accommodate an input voltage up to 18v, it is also suitable for the operation via an ac adapter. ? pc motherboard ? lcd monitor ? graphic card ? dvd-video player ? telecom equipment ? adsl modem ? printer and other peripheral equipment ? microprocessor core supply ? networking power supply ordering information ap1513 xxx package packing - u : tube -13 : taping s : sop-8l lead free l : lead-free g : green note: 1. rohs revision 13.2.2003. glass and high temperature solder exemptions applied, see eu directive annex notes 5 and 7 . tube/bulk 13? tape and reel device package code packaging (note 2) quantity part number suffix quantity part number suffix ap1513s s sop-8l 100 -u 2500/tape & reel -13 note: 2. pad layout as shown on diodes inc. suggested pad layout document ap02001, which can be found on our website at http://www.diodes.com/datasheets/ap02001.pdf . features general description applications
ap1513 pwm control 2a step-down converter ap1513 rev. 2 2 of 8 august 2007 www.diodes.com ? diodes incorporated pin descriptions ( top view ) 1 2 3 4 8 7 6 5 fb output ocset ap1513 output en vss vss v cc sop-8l pin descriptions pin name pin no. description fb 1 feedback pin en 2 power-off pin h: normal operation (step-down operation) l: step-down operation stopped (all circuits deactivated) ocset 3 add an external resistor to set max output current v cc 4 ic power supply pin output 5, 6 switch pin. connect external inductor/diode here. minimize trace area at this pin to reduce emi v ss 7, 8 gnd pin
ap1513 pwm control 2a step-down converter ap1513 rev. 2 3 of 8 august 2007 www.diodes.com ? diodes incorporated block diagram oscillation circuit reference voltage source pwm-switched control circuit + - vss v en en 100ua ocset fb vcc thermal shutdown output absolute maxi mum ratings symbol parameter rating unit v cc v cc pin voltage v ss - 0.3 to v ss + 20 v v fb feedback pin voltage v ss - 0.3 to v cc v v en en pin voltage v ss - 0.3 to v in + 0.3 v v out switch pin voltage v ss - 0.3 to v in + 0.3 v p d power dissipation internally limited mw t j operating junction temperature range -40 to +125 o c t st storage temperature range -40 to +150 o c caution: the absolute maximum ratings are rated values exceeding which the product could suffer physical damage. these values must therefore not be exceeded under any conditions. recommended oper ating conditions symbol parameter min max unit v in input voltage 3.6 18 v i out output current 0 2 a t a operating ambient temperature -20 85 o c
ap1513 pwm control 2a step-down converter ap1513 rev. 2 4 of 8 august 2007 www.diodes.com ? diodes incorporated electrical characteristics (v in = 12v, t a = 25c, unless otherwise specified) symbol parameter conditions min. typ. max. unit v fb feedback voltage i out = 0.1a 0.784 0.8 0.816 v i fb feedback bias current i out = 0.1a - 0.1 0.5 a i sw switch current -- 2.5 - - a i sss current consumption during power off v en = 0v - 10 - a ?v out /v out line regulation v in = 5v~18v - 1 2 % ?v out /v out load regulation i out = 0.1 to 2a - 0.2 0.5 % f osc oscillation frequency measure waveform at sw pin 240 300 400 khz f osc1 frequency of current limit or short circuit protect measure waveform at sw pin 10 - - khz v sh evaluate oscillation at sw pin 2.0 - - v sl en pin input voltage evaluate oscillation stop at sw pin - - 0.8 v i sh -- - 20 - a i sl en pin input leakage current -- - -10 - a i ocset ocset pin bias current -- 75 90 105 a t ss soft-start time -- 0.3 2 5 ms v in = 5v, v fb = 0v - 110 150 r dson internal mosfet rdson v in = 12v, v fb = 0v - 70 100 m ? effi efficiency v in = 12v, v out = 5v i out = 2a - 92 - % ja thermal resistance junction-to-ambient sop-8l (note 3) - 134 - o c/w jc thermal resistance junction-to-case sop-8l (note 3) - 22 - o c/w note: 3. test conditions: device mounted on fr-4 pcb, 2"*2", 2oz copper minimum recommended pad layout, single-sided, pc boa rds.
ap1513 pwm control 2a step-down converter ap1513 rev. 2 5 of 8 august 2007 www.diodes.com ? diodes incorporated typical application circuit ap1513 + - v ss en c c r a r b d1 sbr2u30p1 fb vcc output cvcc v out = 5v/2a v in r ocset ocset c out c in optional c ocset c en r en option 100k note: v out = v fb x (1+r a /r b ) r b =0.7k~5k ohm l1 33uh 6.8k 1.3k 3k 0.1uf + - c 0.1uf 470uf 470uf 0.1uf figure 1. v in = 12v, i max = 2a v out 2.5v 3.3v 5v l1 value 22uh 27uh 33uh typical perform ance characteristics ap1513 vin vs. frequency (vout=3.3v; iout=0.2a) 310 315 320 325 330 335 340 345 350 0 2 4 6 8 10 12 14 16 18 20 vin (v) fosc (khz) ap1513 vin vs. fb (vout=3.3v; iout=0.2a) 0.74 0.75 0.76 0.77 0.78 0.79 0.80 0.81 0.82 0.83 0.84 02468101214161820 vin (v) fb (v)
ap1513 pwm control 2a step-down converter ap1513 rev. 2 6 of 8 august 2007 www.diodes.com ? diodes incorporated typical performance characteristics (continued) ap1513 line regulation (vout=3.3v; iout=0.2a) 3.10 3.15 3.20 3.25 3.30 3.35 3.40 0 2 4 6 8 10 12 14 16 18 20 vin (v) vout (v) ap1513 load regulation (vin=12v) 5.00 5.01 5.02 5.03 5.04 5.05 5.06 5.07 5.08 5.09 5.10 0.0 0.5 1.0 1.5 2.0 2.5 iout (a) vout (v) ap1513 efficiency 0 10 20 30 40 50 60 70 80 90 100 0.0 0.5 1.0 1.5 2.0 iout (a) efficiency (%) vout:5.0v vout:3.3v ap1513 v out ripple ( v in = 12v; v out = 3.3v; i out = 0.1a ) ap1513 v out ripple ( v in = 12v; v out = 3.3v; i out = 2a )
ap1513 pwm control 2a step-down converter ap1513 rev. 2 7 of 8 august 2007 www.diodes.com ? diodes incorporated test circuit a fb vcc vss en open open fb vcc vss en + - oscillation output output a fb vcc vss en + - + - v output ocset ocset ocset enable function test feedback function test operation function test 1k 3k 1.2k 6.8k 1k 33k function description pwm control the ap1513 consists of dc/dc converters that employ a pulse-width modulation (pwm) system. in converters of the ap1513, the pulse width varies in a range from 0 to 100%, according to the load current. the ripple voltage produced by the switching can easily be removed through a filter because the switching frequency remains constant. therefore, these converters provide a low-ripple power over broad ranges of input voltage and load current. under voltage lockout the under voltage lockout circuit of the ap1513 assures that the high-side mosfet driver outputs remain in the off state whenever the supply voltage drops below 3.3v. normal operation resumes once v cc rises above 3.5v. r ds(on) current limiting the current limit threshold is setting by the external resistor connecting from v cc supply to ocset. the internal 100ua sink current crossing the resistor sets the voltage at the pin of ocset. when the pwm voltage is less than the voltage at ocset, an over-current condition is triggered. riri ocset ocset ds(on) load = see above formula for setting the current limit value.
ap1513 pwm control 2a step-down converter ap1513 rev. 2 8 of 8 august 2007 www.diodes.com ? diodes incorporated ( top view ) sop-8l ap1513 yy ww x x logo part no. internal code year : "07" = 2007 "08" = 2008 xth week: 01~52 ~ 5 8 4 1 g : green blank : lead free package information (unit mm ) 1.27typ 0.3/0.5 7~9 4.80/5.30 3.70/4.10 5.79/6.20 0.20typ 7~9 3.70/4.10 0.38/1.27 0.08/0.25 gauge plane 0.254 seating plane 0.35max. 45 detail "a" detail "a" 1.30/1.50 1.75max. important notice life support diodes incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or ot her changes without further notice to any product herein. diodes incorporated does not assume any liability arising out of the application or use of any product described herein; neither does it convey any license under its patent rights, nor the rights of others. the user of products in such applications shall a ssume all risks of such use and will agree to hold diodes incorporated and all the companies whose products are represented on our website, harmless against all dam ages. diodes incorporated products are not authorized for use as critical components in life support devices or systems without the e xpressed written approval of the president of diodes incorporated. marking information
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