AP1522 step-up dc/dc converter AP1522 rev. 3 1 of 9 january 2007 www.diodes.com ? diodes incorporated ap 1522 x x x package packing w : sot25 -7 : taping l : lead-free g : green (note 2) lead-free ? high efficiency: 84% typical ? 36v high output voltage ? fast 1mhz switching frequency ? low profile sot25 pb-free packaging ? sot25: available in ?green? molding compound (no br, sb) ? lead free finish/rohs compliant for lead free and ?green? products (note 1) the AP1522 is a step-up dc/dc converter in a 5-lead low profile sot25 package. the AP1522 switches at 1mhz that allows the use of tiny external components. a low 1.25v feedback voltage minimizes power loss in the current setting resistor for better efficiency. ? cellular phones ? pda?s, hand-held computers ? digital cameras ? lcd bias voltage, battery backup note: 1. rohs revision 13.2.2003. glass and high temperature solder exemptions applied, see eu directive annex notes 5 and 7 . 2. green is for sot25. note: 3. pad layout as shown on diodes inc. suggested pad layout document ap 02001, which can be found on our website at http://www .diodes.com/datasheets/ap02001.pdf. features general description applications ordering information tube -7? tape and reel device (note 3) package code packaging quantity part number suffix quantity part number suffix AP1522w w sot25 5000 -b 3000/tape & reel -7
AP1522 step-up dc/dc converter AP1522 rev. 3 2 of 9 january 2007 www.diodes.com ? diodes incorporated block diagram 1mhz oscillator ramp generator - + - + - + v ref 1.25v v in 5 3 fb r c c c comparator a2 r s q a1 1 driver sw q1 2 gnd 4 shdn shutdown pin assignments pin descriptions name description sw switch pin. connect inductor/diode here. minimize trace area at this pin to reduce emi. v ss gnd pin fb feedback pin. reference voltage is 1.25v. shdn shutdown pin. tie to 0.6v or higher to enable device; 0.5v or less to disable device. v in input supply pin. must be locally bypassed. v in shdn sw v ss fb top view sot25
AP1522 step-up dc/dc converter AP1522 rev. 3 3 of 9 january 2007 www.diodes.com ? diodes incorporated absolute maximum ratings symbol parameter rating unit v in v in pin voltage 10 v v sw sw voltage 36 v v fb feedback pin voltage 10 v v shdn shdn pin voltage 10 v t j maximum junction temperature 125 o c t lead lead temperature (soldering for 10s.) 300 o c t opr operating ambient temperature range 0 to +85 o c t stg storage temperature range -40 to +125 o c caution: the absolute maximum ratings are rated values exceedi ng which the product could suffer physical damage. these values m ust therefore not be exceeded under any conditions. electrical characteristics (t a = 25 c , v in = 5v, v shdn = 5v, unless otherwise noted) symbol parameter conditions min. typ. max. unit v in minimum operation voltage - 2.5 - - v v in maximum operation voltage - - - 10 v v fb feedback pin voltage - 1.225 1.25 1.275 v i fb feedback pin bias current - 10 45 100 na operation current - 2 3 ma i in supply current v shdn = 0v - 0.1 1.0 a f sw switching frequency 0.75 1.0 1.25 mhz duty pwm maximum duty cycle 85 90 - % i sw switch current 280 320 360 ma v sat switch v sat i sw = 250ma - 350 - mv switch leakage current v sw = 5v - 0.1 5 a v shdn shdn pin voltage high enable 0.6 - - v v shdn shdn pin voltage low disable - - 0.5 v i shdn shdn pin bios current - 10 - a
AP1522 step-up dc/dc converter AP1522 rev. 3 4 of 9 january 2007 www.diodes.com ? diodes incorporated typical application circuit v in sw v ss fb shdn on off c1 4.7uf c2 4.7uf r2 10k l1 10uh d1 v out = 10v r1 70k v in = 3.3v option v out = v fb (1+ ) r1 r2 1k < r2 < 50k step up dc-dc regulator v in sw shdn gnd fb AP1522 c out 4.7uf 20k l 22uh d v in 2.5v~3.3v c in 4.7uf 57k v out 4.8v 4.7pf 1-cell li-lon to 3.3v sepic converter v in sw shdn gnd fb AP1522 c2 10uf 20k l1 10uh d1 v in 2.5v to 4.2v c1 4.7uf 33k 3.3v 50ma 1 5 4 2 3 4.7pf l2 10uh c3 1uf
AP1522 step-up dc/dc converter AP1522 rev. 3 5 of 9 january 2007 www.diodes.com ? diodes incorporated typical application circuit (continued) 4-cell to 5v sepic converter v in sw shdn gnd fb AP1522 c2 10uf 10k l1 10uh d1 v in 3v to 6v c1 4.7uf 30k 5v 40ma 1 5 4 2 3 4.7pf l2 10uh c3 1uf + 20v dual output converter with output disconnect v in sw shdn gnd fb AP1522 c2 10uf 10k l1 10uh d1 v in 2.5v to 5v c1 4.7uf 150k 20v 4ma 1 5 4 2 3 4.7pf c5 1uf d4 -20v 4ma d2 d3 c3 1uf c4 1uf
AP1522 step-up dc/dc converter AP1522 rev. 3 6 of 9 january 2007 www.diodes.com ? diodes incorporated applications information inductor selection a 10h inductor is recommended for most AP1522 applications. although small size and high efficiency are major concerns, the inducto r should have low core losses at 1mhz and low dcr (copper wire resistance). capacitor selection the small size of ceramic capacitors makes them ideal for AP1522 applications. x5r and x7r types are recommended because they retain their c apacitance over wider voltage and temperature ranges than other types such as y5v or z5u. a 4.7f input capacitor and a 4.7f output capacitor are sufficient for most AP1522 applications. diode selection schottky diodes, with their low forward voltage drop and fast reverse recovery, are the ideal choices for AP1522 applications. the forward voltage drop of a schottky diode represents the conduction losses in the diode, while the diode capacitance (c t or c d ) represents the switching losses. for diode selection, both forward voltage drop and diode capacitance need to be considered. schottky diodes with higher current ratings usually have lower forward voltage drop and larger diode capacitance, which can cause significant switching losses at the 1mhz switching frequency of the AP1522. a schottky diode rated at 100ma to 200ma is sufficient for most AP1522 applications. open-circuit protection in the cases of output open circuit, when the r1 are disconnected from the circuit, the feedback voltage will be zero. the AP1522 will then switch at a high duty cycle resulting in a high output voltage, which may cause the sw pin voltage to exceed its maximum 36v rating. a zener diode can be used at the output to limit the voltage on the sw pin ( figure 1 ). the zener voltage should be larger than the maximum forward voltage of the v out . the current rating of the zener should be larger than 0.1ma. v in sw shdn gnd fb AP1522 c out 2uf r3 14k l 22uh d v in c in 1uf r2 1k r1 200k 4.7pf figure 1. with open-circuit protection
AP1522 step-up dc/dc converter AP1522 rev. 3 7 of 9 january 2007 www.diodes.com ? diodes incorporated frequency vs. temperature v in = 5v; v out = 15v feedback voltage vs. temperature v in = 5v; v out = 15v 0 100 200 300 400 500 600 700 800 900 1000 -40 10 60 110 frequency (khz) temperature ( o c) 1.22 1.23 1.24 1.25 1.26 -40 10 60 110 feedback voltage (v) tem p erature ( o c ) supply current vs. temperature v in = 5v; v out = 15v; i out = 0a supply current vs. supply voltage v out = 15v; i out = 0a 0 0.5 1 1.5 2 2.5 3 -40 10 60 110 supply current (ma) temperature ( o c) 0 0.5 1 1.5 2 2.5 3 0 5 10 15 supply current (ma) su pp l y vo l ta g e ( v ) efficiency vs. output current v in = 5v; v out = 15v efficiency vs. output current v in = 3.3v; v out = 15v 70 75 80 85 90 0204060 efficiency (%) output current (m a) 55 65 75 85 0204060 efficiency (%) output current (m a) . typical performance characteristics
AP1522 step-up dc/dc converter AP1522 rev. 3 8 of 9 january 2007 www.diodes.com ? diodes incorporated frequency vs. supply voltage v out = 15v 0 200 400 600 800 1000 1200 0 5 10 15 frequency (khz) supply voltage (v) package diagrams (all dimensions in mm) (1) sot25 0.10/0.20 typ 0.15 0.013/0.10 typ 0.05 0.35/0.55 typ 0.40 typ 0.95 1.50/1.70 typ 1.60 2.70/3.00 typ 2.80 2.90/3.10 typ 3.00 1.00/1.30 typ 1.10 typ 0.55 top view typical performance characteristics (continued)
AP1522 step-up dc/dc converter AP1522 rev. 3 9 of 9 january 2007 www.diodes.com ? diodes incorporated marking information (1) sot25 device package (note 4) identification code AP1522w sot25 fa note: 4. for packaging details, go to our website at http://www.diodes.com/datasheets/ap02007.pdf . 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 pr oduct 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. identification code 1 2 3 5 7 4 xx m year: 0-9 month: a~l y x blank : lead free g:green
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