advanced power electronics corp. features description application for extreme low output voltage guaranteed 600ma output current very low quiescent current at about 30ua 1% output voltage accuracy needs only 1f capacitor for stability thermal shutdown / current limited protection adjusted mode with 0.8v reference voltage low-esr ceramic capacitor for output stability. tiny esop-8 package type halogen free product high psrr application s dvd/cd-roms, cd/rws wireless devices lcd modules battery power systems card readers xdsl routers ordering / package information data and specifications subject to change without notice 20130121v1.1 APE8845 typical applicatio n 600ma low dropout linear regulato r 1 the APE8845 series are low dropout, positive linea r regulators with very low quiescent current. the APE8845 can supply 600ma output current with a low dropout voltage & very low output voltage. the APE8845 regulator is able to operate with output capacitors as small as 1 f for stability. other than the current limit protection APE8845 also offers on chip thermal shutdown feature providing protection against overload o r any condition when the ambient temperature exceeds the j unction temperature. the APE8845 series are available in low-profile, space-saving esop-8 packages. note : r 1 ,r 2 for adjusted mode only, 1k < r1+r2 < 90k note : to prevent oscillation, it is recommended to use minimum 1uf x7r or x5r dielectric capacitors if ceramics are used as input / output capacitors. figure1. application of the APE8845-adj v shdn vin gnd vout shdn adj c out c in r 1 r 2 vin vout adj APE8845-adj package type mp : esop-8 APE8845x ( top view ) 1 2 3 4 8 7 6 5 gnd esop-8 vin nc adj vout shdn nc nc gnd rthja=40 /w rthjc=15 /w
advanced power electronics corp. APE8845 absolute maximum ratings input voltage (v in ) ----------------------------------------- - 6v power dissipation ------------------------------------------ - 0.625w storage temperature range ---------------------------- -65c to 150c maximum junction temperature ----------------------- - 150c recommended operating conditions input voltage (v in ) ----------------------------------------- - 2.8 to 5.5v operating junction temperature range (t j ) ------- - -40 to 125 o c ambient temperature (t a ) ------------------------------- - -40 to 85 o c electrical specifications ( v in =v out +1v or v in =2.8v whichever is greater, c in =1uf, c out =1uf, t a =25 o c, unless otherwise specified) parameter sym test condition min typ max units output voltage accuracy ? ? ? ?
advanced power electronics corp. pin descriptions pin symbol gnd adj nc shdn the larger output capacitor will be required for application with large transit load to limit peak voltage transits, besides could reduce output noise, improve stability, psrr. chip enable (active high) pin description power is supplied to this device from this pin which is required an input filter capacitor. in general, the input capacitor in the range of 1f to 10f is sufficient. the output supplies power to loads. the output capacitor is required to prevent output voltage unstable. the common ground pin no connected for adjusted mode, apply r 1 /r 2 resistor divider with vout to gnd vout APE8845 3 block diagram vin APE8845 is stable with an output capacitor 1f to 10f. figure 2. block diagram of APE8845 v out = 0.8 x (1+r 1 /r 2 ) shdn 1.6k
advanced power electronics corp. application informatio output & input capacitor protection features thermal consideration APE8845 4 the APE8845 series are low dropout linear regulators that could provide 600ma output current at dropout voltage about 800mv. besides, current limit and on chip thermal shutdown features provide protection against any combination of overload or ambient temperature that could exceed j unction temperature. the APE8845 regulator is designed to be stable with a wide range of output capacitors. the esr of the output capacitor affects stability. larger value of the output capacitor decreases the peak deviations and provides to improve transition response for larger current changes. the capacitor types (aluminum, ceramic, and tantalum) have different characterizations such as temperature and voltage coefficients. all ceramic capacitors are manufactured with a variety o f dielectrics, each with different behavior across temperature and applications. common dielectrics used are x5r, x7r and y5v. it is recommended to use 1uf to 10uf x5r or x7r dielectric ceramic capacitors with 30 mohm to 50 mohm esr range between device outputs to ground for transient stability. the APE8845 is designed to be stable with low esr ceramic capacitors and higher values o f capacitors and esr could improve output stability. so the esr of output capacitor is very importart because it generates a zero to provide phase lead for loop stability. there are no requirements for the esr on the input capacitor, but its voltage and temperature coefficient have to be considered for device application environment. in order to prevent overloading or thermal condition from damaging the device, APE8845 regulator has internal thermal and current limiting functions designed to protect the device. it will rapidly shut off pmos pass element during overloading or over temperature condition. the power handling capability of the device will be limited by maximum operation junction temperature (125c). the power dissipated by the device will be estimated by p d =i out (v in -v out ). the power dissipation should be lower than the maximum power dissipation listed in ? absolute maximum ratings? section.
advanced power electronics corp. APE8845 typical performance characteristics 5 load transient v in =4v, i out =1ma~600ma, t a =25 o c i q vs. temperature 41 41.5 42 42.5 43 43.5 44 44.5 45 45.5 46 46.5 -40 -25 0 25 50 75 100 115 tem perature( o c) quiescent current, i q (ua) i q vs. v in 44.15 44.65 45.15 45.65 46.15 46.65 4.3 4.5 4.7 5 input voltage, v in (v) quiescent current, i q (ua) v out vs. temperature 3.1 3.15 3.2 3.25 3.3 3.35 3.4 -40-20 0 255085105125 tem perature( o c) v out (mv) 1m a 300m a load regulation 2 2.2 2.4 2.6 2.8 3 0 1 10 50 100 200 300 400 500 600 i out (m a) v out (v) line regulation 0 0.5 1 1.5 2 2.5 3 3.5 4.3 4.5 4.7 5 v in (v ) v out (v) v out i out
advanced power electronics corp. APE8845 typical performance characteristics enable off test power on test power off test v in =4v, v out =2.5v, i out =600ma, 6 psrr enable on test v in =3.3v, v out =2.5v, i out =600ma, v in v out i out v in v out i out v en v out i out v en v out i out
advanced power electronics corp. marking information esop-8 7 APE8845 8845mp ywwsss part number date code (ywwsss) y ? last digit of the year ww ? week sss ? sequence package code
|
