advanced power electronics corp. 1a ultra low dropout linear regulator feature s description ultra low dropout - 0.2v(typical) at 1a output current low esr output capacitor (multi-layer chip capacitors (mlcc)) applicable 0.8v reference voltage fast transient response adjustable output voltage by external resistors power-on-reset monitoring on both vcntl and vin pins internal soft-start under-voltage protection current-limit and thermal shutdown protection power-ok output with a delay time esop-8 and dfn 2x2 pb-free packages. typical application circuit 1. using an output capacitor with esr > 20m ? 2. using an mlcc as the output capacitor data and specifications subject to change without notice 201010203 ape8901 1 the ape8901 is a 1a ultra low dropout linear regulator. this product is specifically designed to provide well supply voltage for front-side-bus termination on motherboards and nb applications. the ic needs two supply voltages, a control voltage for the circuitry and a main supply voltage for power conversion, to reduce power dissipation and provide extremely low dropout. the ape8901 integrates many functions. a power-on-reset (por) circuit monitors both supply voltages to prevent wrong operations. a thermal shutdown and current limit functions protect the device against thermal and current over-loads. a pok indicates the output status with time delay which is set internally. it can control other converter for power sequence. the ape8901 can be enabled by other power system. pulling and holding the en pin below 0.3v shuts off the output. the ape8901 is available in esop-8 and dfn 2x2 packages. that features small size as sop-8 with an exposed pad to reduce the junction-to-case resistance, being applicable in 2~3w applications. c1 1uf r1 1k vout=1.2v/1a vin=1.5v r3 1k vcntl=5v c4 220uf c5 0.1u u1 ape8901 vcntl fb vout gnd nc en pok vin c2 100uf c3 0.1uf c6 12~48nf r2 2k off on vin=1.5v r3 1k vout=1.2v/1a u2 ape8901 vcntl fb vout gnd nc en pok vin c6 56pf c5 22u c1 1uf c3 22uf vcntl=5v r2 78k r1 39k off on vfb =0.8v vout=vfb x (1+r1/r2)
advanced power electronics corp. ape8901 absolute maximum ratings (at t a =25 o c) vcntl supply voltage (v cntl ) -------------------------- - -0.3v to 7v vin supply voltage (v in ) ---------------------------------- -0.3v to 6v en & fb pin voltage (vi/o) ------------------------------ - -0.3v to vcntl+0.3v power voltage (v pok ) -------------------------------------- - -0.3v to 7v power dissipation (p d ) esop-8 ------ - 3w dfn 2x2 ----- - 0.8w storage temperature range (t st ) --------------------- - -65c to 150c junction temperature range (t j ) ---------------------- - -40c to 125c operating temperature range (t op ) ------------------ - -40c to 85c thermal resistance junction to ambient (rth ja ) esop-8 ------ - 40c/w dfn 2x2 ----- - 125c/w thermal resistance junction to case (rth jc ) esop-8 ------ - 15c/w dfn 2x2 ----- - 20c/w recommended operating conditions v cntl supply voltage (vcntl) -------------------------- 3v to 6v vin supply voltage (v in ) ---------------------------------- 1v to 5.5v output voltage (v out ) -------(v cntl -v out > 1.9v)---- - 0.8v to 2.8v output current (i out ) -------------------------------------- - 0 to 1a ordering / package information 2 note. rth ja is measured with the pcb copper area (need connect to expose-pad) of approximately 1.5 in 2 (multi-layer) by esop-8 and dfn-8l packages. package type mp : esop-8 ape8901x gn2 : dfn 2x2 ( top view ) 1 2 3 4 8 7 6 5 nc vout esop-8 gnd fb en pok vin vcntl gnd dfn 2x2 vout pok vin 12 3 4 5 6 en nc fb (top view) 7 8 vcntl gnd gnd
advanced power electronics corp. ape8901 electrical specifications (v cntl = 5v, v in = 1.5v, v out = 1.2v, t a =25 o c unless otherwise specified) parameter sym test condition min typ max units vcntl por threshold v cntl 2.5 2.7 2.9 v vcntl por hysteresis v cntl(hys) - 0.4 - v vin por threshold v in 0.8 0.9 1 v vin por hysteresis v in(hys) - 0.5 - v vcntl nominal supply current i cntl en= v cntl 0.4 1 2 ma vcntl shuntdown current i sd en= 0v - 10 30 ua feedback voltage v fb v cntl =3 ~ 6.0v 0.784 0.8 0.816 v load regulation i out =0a ~ 1a - 0.06 0.25 % v out <2.0v,i out =1a - 200 250 2.0v advanced power electronics corp. ape8901 block diagram pin description fb vin vcntl pok en 4 connecting this pin to an external resistor divider receives the feedback voltage of the regulator. the output voltage set by the resistor divider is determined by: where r1 is connected from vout to fb with kelvin sensing and r2 is connected from fb to gnd. a bypass capacitor may be connected with r1in parallel to improve load transient response. the recommended r2 and r1 are in the range of 1k~100k ? . main supply input pins for power conversions. the voltage at this pin is monitored for power- on reset p ur p ose. power input pin of the control circuitry. connecting this pin to a +5v (recommended) supply voltage provides the bias for the control circuitry. the voltage at this pin is monitored for power-on reset purpose. power-ok signal output pin. this pin is an open-drain output used to indicate status of output voltage by sensing fb voltage. this pin is pulled low when the rising fb voltage is not above the vpok threshold or the falling fb voltage is below the vpok threshold, indicating the output is not ok. enable control pin. pulling and holding this pin below 0.4v shuts down the output. when re- enabled, the ic undergoes a new soft-start cycle. left this pin open, this pin is internal pulled up to vcntl voltage, enabling the regulator. - + vin vout gnd error amp en vcntl soft-start and control logic power -on reset current limit enable thermal shutdown bandgap fb -+ pok delay pok - + uv 0.4v 90% vref n-mosfet 90
advanced power electronics corp. ape8901 pin description vout function description power-on-reset internal soft-start output voltage regulation current-limit under-voltage protection (uvp) thermal shutdown 5 output of the regulator. please connect pin 6 using wide tracks. it is necessary to connect an output capacitor with this pin for closed-loop compensation and improving transient responses. a power-on-reset (por) circuit monitors both input voltages at vcntl and vin pins to prevent wrong logic controls. the por function initiates a soft-start process after the two supply voltages exceed their rising por threshold voltages during powering on. the por function also pulls low the pok pin regardless the output voltage when the vcntl voltage falls below its falling por threshold. an internal soft-start function controls rise rate of the output voltage to limit the current surge at start-up. the typical soft-start interval is about 2ms. an error amplifier working with a temperature compensated 0.8v reference and an output nmos regulates output to the preset voltage. the error amplifier designed with high bandwidth and dc gain provides very fast transient response and less load regulation. it compares the reference with the feedback voltage and amplifies the difference to drive the output nmos which provides load current from vin to vout. the ape8901 monitors the current via the output nmos and limits the maximum current to prevent load and ape8901 from damages during overload or short circuit conditions. the ape8901 monitors the voltage on fb pin after soft-start process is finished. therefore the uvp is disabling during soft-start. when the voltage on fb pin falls below the under-voltage threshold, the uvp circuit shuts off the output immediately. after a while, the ape8901 starts a new soft-start to regulate output. a thermal shutdown circuit limits the junction temperature of ape8901. when the junction temperature exceeds +150c, a thermal sensor turns off the output nmos, allowing the device to cool down. the regulator regulates the output again through initiation of a new soft-start cycle after the junction temperature cools by 40c, resulting in a pulsed output during continuous thermal overload conditions. the thermal shutdown designed
advanced power electronics corp. ape8901 typical performance characteristics 6 0 0.5 1 1.5 2 2.5 3 3 3.5 4 4.5 5 5.5 6 vcntl (v) vcntl supply current (ma) vcntl supply current vin=1.5v vout=1.2v no load 0 10 20 30 40 50 33.544.555.56 vcntl (v) vcntl shutdown current (ua) vcntl shutdown current 0.74 0.76 0.78 0.8 0.82 0.84 0.86 3 3.5 4 4.5 5 5.5 6 vcntl (v) feedback voltage (v) vcntl vs feedback voltage vin=1.5v vout=1.2v load=100ma 0 0.5 1 1.5 2 2.5 3 3.5 4 -40 -20 0 25 50 85 105 125 temperature () vcntl supply current (ma) temperature vs vcntl supply current vin=1.5v vcntl=5v vout=1.2v no load 0.76 0.77 0.78 0.79 0.8 0.81 0.82 0.83 0.84 3 3.5 4 4.5 5 5.5 6 load (ma) feedback voltage (v) load vs feedback voltage vin=1.5v vcntl=5v vout=1.2v 0 100 200 300 400 500 600 0 200 400 600 800 1000 load (ma) dropout voltage (mv) load vs dropout vcntl=5v vout=1.2v vout=3.0v vout=2.5v vout=1.8v
advanced power electronics corp. ape8901 typical performance characteristics load transient (vin=1.5v, vcntl=5v,vout=1.2v,laod=1a) enable ?off (vin=1.5v, vcntl=5v,vout=1.2v,no laod) (vin=1.5v, vcntl=5v,vout=1.2v,laod=1a) (vin=1.5v, vcntl=5v,vout=1.2v,laod=10m~1a) 7 enable ?on power ?on 0.75 0.76 0.77 0.78 0.79 0.8 0.81 0.82 0.83 0.84 0.85 -40 -20 0 25 50 85 105 125 temperature () feedback voltage (v) temperature vs feedback voltage vin=1.5v vcntl=5v vout=1.2v load=10ma 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3 -40 -20 0 25 50 85 105 125 temperature () vcntl uvlo (v) temperature vs vcntl uvlo rising falling v out i out v cntl en v out i in v cntl en v out i in en v out
advanced power electronics corp. ape8901 marking information esop-8 8 part number date code (ywwsss) y last digit of the year ww week sss sequence package code 8901mp ywwsss h3 xxx part number : h3 date code
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