advanced power electronics corp. features description ultra low dropout - 0.23v(typical) at 3a 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 3x3-10l pb-free package. 1.using an output capacitor with esr > 20m ? 2.using an mlcc as the output capacitor esop- 8 data and specifications subject to change without notice 201005311 ape8973 3a ultra low dropout linear regulator typical application 1 the ape8973 is a 3a 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 ape8973 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 ape8973 can be enabled by other power system. pulling and holding the en pin below 0.3v shuts off the output. the ape8973 is available in esop-8 and dfn 3x3- 10l packages which features small size as an exposed pad to reduce the junction-to-case resistance, being applicable in 2~3w applications. c1 1uf r1 1k vout=1.2v/3a vin=1.5v r3 1k vcntl=5v c4 220uf c5 0.1u u1 ape8973 vcntl fb vout gnd en pok vin c2 100uf c3 0.1uf c6 12~48nf r2 2k off on vout vin=1.5v r3 10k vout=1.2v/3a vfb = 0.8v u2 ape8973mp vcntl fb vout gnd en pok vin c6 56pf c5 10uf c1 1uf c3 10uf vout=vfb*(1+r1/r2) vcntl=5v r2 78k r1 39k off on vout
advanced power electronics corp. ape8973 2.using an mlcc as the output capacitor dfn 3x3-10l absolute maximum ratings (at t a =25c) vcntl supply voltage(v cntl ) ------------------------- - -0.3v to 7v vin supply voltage(v in ) --------------------------------- - -0.3v to 7v en and fb pin voltage(v i/o ) ---------------------------- -0.3v to v cntl +0.3v power good voltage(v pok ) ----------------------------- - -0.3v to 7v power dissipation(p d ) ------------------------------------ - 3w storage temperature range(t st ) --------------------- -65c to +150c junction temperature range(t j ) --------------------- - -40c to 150c operating temperature range (t op ) ----------------- - -40c to +85c thermal resistance from junction to case(rth jc ) 15c/w 40c/w recommended operating conditions vcntl supply voltage(v cntl ) ------------------------- - 3v to 6v vin supply voltage(v in ) --------------------------------- - 1.2v to 6v output voltage(v out ) ------------------------------------- - 0.8v to v in -v drop (v cntl - v out > 1.4v) output current(i out ) -------------------------------------- - 0 to 3a note: rth ja is measured with the pcb copper area (need connect to expose-pad) of approximately 1.5 in 2 (multi-layer) ordering/package information typical application 2 thermal resistance from junction to ambient(rth ja ) vin=1.5v r3 10k vout=1.2v/3a vfb = 0.8v u2 ape8973gn3 vcntl fb vout gnd en pok vin c6 56pf c5 10uf c1 1uf c3 10uf vout=vfb*(1+r1/r2) vcntl=5v r2 78k r1 39k off on vout vin package type ape8973x mp : esop-8 gn3 : dfn 3x3-10l ( top view ) 1 2 3 4 8 7 6 5 vout esop-8 en pok fb gnd vin vcntl vout exposed pad dfn 3x3-10l fb 1 en 10 2 3 4 5 6 7 8 9 vin vin pok gnd vout vout nc (gnd) vcntl
advanced power electronics corp. ape8973 electrical specifications (v cntl = 5v, v in = 1.5v, v out = 1.2v, t a =25c 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 - 1 1.8 ma vcntl shuntdown current i sd en= 0v - 50 100 ua load regulation i out =0a ~ 3a - 0.06 0.25 % 1.2v Q Q pin descriptions pin symbol pin description gnd gnd pin fb feedback pin internal pull high. en=high or floating enable en=low shutdown mode vout output voltage pin pok power ok output pin vcntl cntl pin input voltage vcc input voltage ep connect to vin or gnd 3 ripple rejection psrr f=120hz, i out =100ma db en c -a current limit i lim 3.3 - en pin logic high threshold voltage v dropout voltage v drop v feedback voltage v fb v cntl =3.0 ~ 6.0v, i out =10ma 0.784 0.8 0.816 v vin vcntl i out = 3a, v cntl =5v
advanced power electronics corp. ape8973 block diagram function pin description fb vout = 0.8 x (1 + r1/r2) vin vcntl pok en vout 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 ?
advanced power electronics corp. ape8973 function description power-on-reset internal soft-start current limit output voltage regulation under voltage protection (uvp) thermal shutdown 5 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 out p ut nmos which p rovides load current from vin to vout. the ape8973 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 ape8973 starts a new soft-start to regulate output. a thermal shutdown circuit limits the junction temperature of ape8973. when the j unction 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 50c, resulting in a pulsed output during continuous thermal overload conditions. the thermal shutdown designed. 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. the ape8973 monitors the current via the output nmos and limits the maximum current to prevent load and ape8973 from damages during overload or short circuit conditions.
advanced power electronics corp. ape8973 typical performance characteristics 6 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 33.544.555.5 v cntl vs i cntl v cntl (v) i cntl (ma) iout=0a 0.790 0.792 0.794 0.796 0.798 0.800 0.802 0.804 0.806 0.808 0.810 3 3.5 4 4.5 5 5.5 v cntl vs vfb v cntl (v) vfb (v) 0.785 0.790 0.795 0.800 0.805 0.810 0.815 00.511.522.53 iout vs vout iout (a) vout (v) v cn tl =5v, vin=1.5v 0.75 0.76 0.77 0.78 0.79 0.80 0.81 0.82 0.83 0.84 0.85 -40 -25 0 25 50 75 100 125 temperaute vs vfb temperature() vfb(v) 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 -40 -25 0 25 50 75 100 125 temperaute vs i cntl temperature() i cntl (ma)
advanced power electronics corp. ape8973 typical performance characteristics 7 enable-on power ok wave output discharge load transient
package outline : esop-8 millimeters symbols min nom max a 5.80 6.00 6.20 b 4.80 4.90 5.00 c 3.80 3.90 4.00 d 048 e 0.40 0.65 0.90 f 0.19 0.22 0.25 m 0.00 0.08 0.15 0.35 0.42 0.49 l 1.35 1.55 1.75 j k g p 3.15 3.25 3.35 q 2.25 2.35 2.45 1.all dimension are in millimeters. 2.dimension does not include mold protrusions. part marking information & packing : esop-8 1.27 typ. h advanced power electronics corp. 0.375 ref. 45 j l 8973mp ywwsss package code part number date code (ywwsss) y last digit of the year ww week sss sequence b a2 i p q
(2) dfn 3x3-10l e d pin 1 indent a a1 a3 y e1 e d1 l (top view) (bottom view) 1 10 1 10 c 0.10 e1 b seating plane dimensions in millimeters dimensions in inches symbol min. nom. max. min. nom. max. a - - 0.90 - - 0.036 a1 0.00 0.02 0.05 0.000 0.001 0.002 a3 0.20 ref. 0.008 ref. b 0.18 0.25 0.30 0.007 0.010 0.012 d 2.90 3.00 3.10 0.114 0.118 0.122 d1 1.10 1.20 1.30 0.043 0.047 0.051 e 2.90 3.00 3.10 0.114 0.118 0.122 e1 2.10 2.20 2.30 0.083 0.087 0.091 l 0.45 0.55 0.65 0.018 0.022 0.026 e 0.50 bsc. 0.020 bsc. e1 2.00 bsc. 0.079 bsc. y 0.00 - 0.08 0.000 - 0.003 date code (ywws) y advanced power electronics corp. ape8973
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