advanced power electronics corp. features description very low supply current regulated output voltage wide range of output voltage is available from 2.2v to 5.0v by 0.1v steps output voltage accuracy 5% output current up to 100ma low ripple and low noise very low start-up voltage high efficiency (vout = 5v typ. 87%) few external components low profile: sot-23, sot-89 & sot-23-5l pb-free data and specifications subject to change without notice 201208301 ape2903 typical application ordering information 1 micropower vfm step-up dc/dc converte r the ape2903 is a high efficiency vfm step-up dc/dc converter for small, low input voltage or battery powered systems with ultra-low quiescent supply current. the a pe2903 accept a positive input voltage from start-up voltage to vout and convert it to a higher output voltage in the 2.2v to 5v range. the ape2903 combine ultra low quiescent supply current and high efficiency to give maximum battery life. the high switching frequency and the internally limited peak inductor current permits the use of small, low cost inductors. only three external components are needed an inductor a diode and an output capacitor. the ape2903 is suitable to be used in battery powered equipment where low noise, low ripple and ultra low supply current are required. the ape2903 is available in very small package: sot-23, sot-89 & sot-23-5l. typical applications are pagers, cameras & video camera, cellular telephones, wireless telephones, palmtop computer, battery backup supplies, battery powered equipment. 47uh d1 b140 c 3 47uf vin ape2903 sw gnd nc nc vout 100uf c 1 out l1 0.1uf c2 0.1uf c4 package type y5 : sot-23-5l ape2903x - xx 25 : 2.5v 50 : 5.0v vout 26 : 2.6v 27 : 2.7v : n : sot-23 g : sot-89 22 : 2.2v
advanced power electronics corp. ape2903 absolute maximum ratings (t a = 25 o c) vin supply voltage(v in ) ---------------------------------- - 5.5 v sw voltage(v sw ) ------------------------------------------- 5.5 v out voltage(v out ) ---------------------------------------- - 5.5 v power dissipation(p d ) ------------------------------------ - ( t j -t a ) / rth ja w storage temperature range(t st ) --------------------- - -40c to 150c operating junction temperature range(t op ) ------ - -20c to + 100c note. rth ja is measured with the pcb copper area of approximately 1 in 2 (multi-layer) that need connect to gnd pin of the ape2903. package information electrical specifications ( v in =1.8v, v out =3v, i out =10ma, t a =25 o c, unless otherwise specified) parameter sym test condition min typ max units output voltage accuracy v out -5 - 5 % start-up voltage(v in -v f ) (note) v start-up i out =1ma, v in =rising from 0 to 2v - 0.65 0.9 v hold-on voltage v hold i out =1ma, v in =falling from 2 to 0v 0.6 - - v supply current i supply no load - 22 - ua internal switch r dson r lx(dson i lx =150ma - 850 - m internal leakage current i lx(leak v lx =4v, forced v out =3.8v - - 0.5 ua maximum oscillator frequency f osc - 150 - khz oscillator duty on d on to be measure on sw pin - 77 - % v out =2.5v~3.0v, i out =50ma - 82 - % v out =3.1v~4.0v, i out =50ma - 83 - % v out =4.1v~5.0v, i out =50ma - 87 - % note : the minimum input voltage for the ic start-up is strictly a function of the vf catch diode. pin descriptions pin symbol pin description sw switch pin. connect external inductor & diode here. gnd gnd pin vout output voltage 2 efficiency rth jc =180 o c/w rth ja =250 o c/w rth jc =100 o c/w rth ja =160 o c/w rth jc =180 o c/w rth ja =250 o c/w sw vout top view sot-23 1 2 3 gnd nc nc sw gnd out top view sot-23-5l 1 2 3 4 5 sw gnd vout top view sot-89-3l 123 tab is vout
advanced power electronics corp. ape2903 block diagram operation application information input/output capacitor selection 3 the ape2903 architecture is built around a vfm control logic core, switching frequency is set through a built in oscillator. t on time is fixed (typ. 5us) while t off time is determined by the error amplifier output, a logic signal coming from the comparison made by the error amplifier stage between the signal coming from the output voltage divide r network and the internal band-gap voltage reference (vref). t off reaches a minimum (typ. 1.7us) when heavy load conditions are met (clock frequency 150 khz). an ove r current conditions, through the internal power switch, causes a voltage drop v lx =r dson x i sw and the v lx limiter block forces the internal switch to be off, so narrowing ton time and limiting internal power dissipation. in this case the switching frequency may be highe r than the 150 khz set by the internal clock generator. vfm control ensures very low quiescent current and high conversion efficiency even with very light loads. since the output voltage pin is also used as the device supply voltage, the versions with higher output voltage present an higher internal supply voltage that results in lower power switch r dson , slightly greater output power and highe r efficiency. moreover, bootstrapping allows the input voltage to sag to 0.6v (at i out =1ma) once the system is started. if the input voltage exceeds the output voltage, the output will follow the input, however, the input or output voltage must not be forced above 5.5v. the output ripple voltage, as well as the efficiency, is strictly related to the behavio r of these elements. the output ripple voltage is the product of the peak inductor current and the output capacitor equivalent series resistance (esr). best performances are obtained with good high frequency characteristics capacitors and low esr. the best compromise for the value of the output capacitance is 47f tantalum capacitor; lowe r values may cause higher output ripple voltage and lower efficiency without compromising the functionality of the device. an input capacitor is required to compensate, if present, the series impedance between the supply voltage source and the input voltage of the application. sw gnd - + vfm control driver - + v ref vout error amp. limiter amp.
advanced power electronics corp. ape2903 inductor selection diode selection pcb layout guide 4 schottky diodes with higher current ratings usually have lower forward voltage drop, larger diode capacitance and fast reverse recovery, it is the ideal choices for ape2903 applications. the forward voltage drop of a schottky diode represents the conduction losses in the system, 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. when laying out the pc board, the following suggestions should be taken to ensure proper operation of the ape2903. these items are also illustrated graphically in below. 1. the power traces, including the gnd trace, the sw trace and the v cc trace should be kept short, direct and wide to allow large current flow. put enough multiply-layer pads when they need to change the trace layer. 2. do not trace signal line under inductor. a47 h inductor is recommended for most ape2903 applications. however, the inductance value is not critical, and the ape2903 will work with inductors in the 33h to 120h.
advanced power electronics corp. ape2903 typical performance characteristics 5
advanced power electronics corp. ape2903 typical performance characteristics 6
advanced power electronics corp. ape2903 marking information sot-23-5l sot-89 sot-23 7 t&3ss part number : t&3 (see identification code) date code : ss ss:2004,2008,2012? ss :2003,2007,2011? s s:2002,2006,2010? ss :2001,2005,2009? 2903& part number output voltage : (see identification code) ywws date code (ywws) y : year ww : week s : sequence part number identification code part number identification code ape2903y5-2.2v to3 ape2903y5-3.8v tn3 ape2903y5-2.5v ta3 ape2903y5-3.9v to3 ape2903y5-2.6v tb3 ape2903y5-4.0v tp3 ape2903y5-2.7v tc3 ape2903y5-4.1v tq3 ape2903y5-2.8v td3 ape2903y5-4.2v tr3 ape2903y5-2.9v te3 ape2903y5-4.3v ts3 ape2903y5-3.0v th3 ape2903y5-4.4v tt3 ape2903y5-3.1v tg3 ape2903y5-4.5v tu3 ape2903y5-3.2v tf3 ape2903y5-4.6v tv3 ape2903y5-3.3v ti3 ape2903y5-4.7v tw3 ape2903y5-3.4v tj3 ape2903y5-4.8v tx3 ape2903y5-3.5v tk3 ape2903y5-4.9v ty3 ape2903y5-3.6v tl3 ape2903y5-5.0v tz3 ape2903y5-3.7v tm3 part number identification code part number identification code ape2903g-2.2v o ape2903g-3.8v n ape2903g-2.5v a ape2903g-3.9v o ape2903g-2.6v b ape2903g-4.0v p ape2903g-2.7v c ape2903g-4.1v q ape2903g-2.8v d ape2903g-4.2v r ape2903g-2.9v e ape2903g-4.3v s ape2903g-3.0v h ape2903g-4.4v t ape2903g-3.1v g ape2903g-4.5v u ape2903g-3.2v f ape2903g-4.6v v ape2903g-3.3v i ape2903g-4.7v w ape2903g-3.4v j ape2903g-4.8v x ape2903g-3.5v k ape2903g-4.9v y ape2903g-3.6v l ape2903g-5.0v z ape2903g-3.7v m t&3ss part number : t&3 (see identification code) date code : ss ss:2004,2008,2012? ss :2003,2007,2011? s s:2002,2006,2010? ss :2001,2005,2009? part number identification code part number identification code ape2903n-2.2v to3 ape2903n-3.8v tn3 ape2903n-2.5v ta3 ape2903n-3.9v to3 ape2903n-2.6v tb3 ape2903n-4.0v tp3 ape2903n-2.7v tc3 ape2903n-4.1v tq3 ape2903n-2.8v td3 ape2903n-4.2v tr3 ape2903n-2.9v te3 ape2903n-4.3v ts3 ape2903n-3.0v th3 ape2903n-4.4v tt3 ape2903n-3.1v tg3 ape2903n-4.5v tu3 ape2903n-3.2v tf3 ape2903n-4.6v tv3 ape2903n-3.3v ti3 ape2903n-4.7v tw3 ape2903n-3.4v tj3 ape2903n-4.8v tx3 ape2903n-3.5v tk3 ape2903n-4.9v ty3 ape2903n-3.6v tl3 ape2903n-5.0v tz3 ape2903n-3.7v tm3
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