advanced power electronics corp. 2.5a linear regulator feature s descriptioon sink and source up to 2.5amp integrated power mosfets high accuracy output voltage at full-load output adjustment by two external resistors built-in soft-start function current limiting protection on-chip thermal protection available in esop-8 (exposed pad) packages v in and v cntl under voltage protection rohs compliant and 100% lead (pb)-free halogen free product applicatio n desktop pcs, notebooks, and workstations graphics card memory termination set top boxes, digital tvs, printers embedded systems active termination buses data and specifications subject to change without notice 20130104v1.1 ape8977mp typical application 1 the ape8977mp is a simple, cost-effective and high-speed linear regulator. the regulator is capable o f actively sinking or sourcing up to 2.5a while regulating an output voltage to within 40mv. the desired output voltage can be programmed by two external voltage divider resistors of the refen pin. the ape8977mp also incorporates a high-speed differential amplifier to provide ultra-fast response in line/load transient. other features include extremely low initial offset voltage, excellent load regulation, current limiting in bi-directions and on-chip thermal shut-down protection. built-in soft-start function avoids a mis- operation by inrush current. the ape8977mp are available in the esop-8 (exposed pad) surface mount packages. vin shutdown enable vcntl vout vin refen vcntl vout gnd r1 r2 css cin ccntl cout rdummy rtt ape8977mp r1 = r 2 = 100 k ,rtt =50 /33 /25 cout = 10 uf ( + 100 uf under the worst case testing condition ) css = 1 uf , cin = 470 uf (low esr ) , ccntl = 47 uf
advanced power electronics corp. ape8977mp absolute maximum ratings (note1) input voltage (v in ) ----------------------------------------- - 6v cntl pin voltage (v cntl ) ------------------------------- - 6v power dissipation (p d ) ----------------------------------- - internally limited storage temperature range (t st ) -------------------- - -65 to +150c lead temperature (soldering, 10sec.) --------------- - 260c 28c/w note1 : exceeding the absolute maximum rating may damage the device. operating rating (note2) input voltage (v in ) ----------------------------------------- - 2.5v to 1.5v + 3% cntl pin voltage (v cntl ) ------------------------------- - 5.5v or 3.3v + 5% junction temperature range (t j ) --------------------- - -40 to +125c ambient temperature range (t a ) --------------------- -40 to +85c note2 : the device is not guaranteed to function outside its operating conditions. ordering / package information (v in =1.8v, v cntl =3.3v, v refen =0.9v, c out =10uf(ceramic), t a =25 o c, unless otherwise specified) parameter sym test condition min typ max units vcntl operation current i cntl i out = 0a - 1 2.5 ma standby current i stby v refen= 0v (shutdown) - 25 ua vin shutdown current i vin v refen= 0v (shutdown) - - 5 ua vcntl uvp rising threshold v cop v cntl rising 2.4 2.55 2.7 v vcntl uvp hysteresis v chys - 0.35 -v vin uvp rising threshold v iop v iop rising 0.8 0.95 1.1 v vin uvp hysteresis v ihys - 0.15 -v i out = 10ma -20 - 20 i out = -10ma -20 - 20 i out = 10ma ~ 2a -20 - 20 i out = -10ma ~ -2a -20 - 20 2 thermal resistance from junction to case (r thjc ) output (ddr / ddrii / ddriii) load regulation (note4) v load mv uvp function output offset voltage (note3) v load electrical specifications input ( top view ) 1 2 3 4 8 7 6 5 refen esop-8 nc nc gnd vin nc vcntl vout gnd r th j a = 75 o c/w ape8977x package type mp : esop-8
advanced power electronics corp. ape8977mp parameter sym test condition min typ max units current limit i lim v cntl =5v, v in =1.5v, v out =1.0v 2.5 - - a thermal shutdown temperature t sd 3.3v < v cntl < 5v - 150 - thermal shutdown hysteresis t sd 3.3v < v cntl < 5v - 20 - refen threshold v en 0.15 - 0.4 v soft-start interval t ss ? v out =1v - 0.8 - ms note3. v os offset is the voltage measurement defined as v out subtracted from v refen . note4. regulation is measured at constant junction temperature by using a 1ms(on) / 9ms(off) current pulse. devices are tested for load regulation in the load range from 10ma to 2a for source and -10ma to -2a for sink capability. pin descriptions pin symbol pin description vin power input voltage. gnd ground pin vout output voltage vcntl gate drive voltage refen reference voltage input and chip enable block diagram 3 electrical specification s enable and soft-start protection o c vcntl enable function soft-start function gate control logic ocp function uvp function otp function refen vin vout gnd error amplifier
advanced power electronics corp. ape8977mp application information input capacitor and layout consideration consideration while designs the resistance of voltage divider thermal consideration 4 make sure the sinking current capability of pull-down nmos if the lower resistance was chosen so that the voltage on v refen is below 0.15v. in addition, the capacitor and voltage divider form the lowpass filter. there are two reasons doing this design; one is for output voltage soft- start while another is for noise immunity. ape8977mp regulators have internal thermal limiting circuitry designed to protect the device during overload conditions.for continued operation, do not exceed maximum operation junction temperature 125 o c. the power dissipation definition in device is: p d = (v in - v out ) x i out + v in x i q the maximum power dissipation depends on the thermal resistance of ic package, pcb layout, the rate of surroundings airflow and temperature difference between junction to ambient. the maximum power dissipation can be calculated by following formula: p d(max) = ( t j(max) -t a ) / r thja where t j(max) is the maximum operation junction temperature 125 o c, t a is the ambient temperature and the r thja is the junction to ambient thermal resistance. the junction to ambient thermal resistance (r thja is layout dependent) for esop-8 package (exposed pad) is 75 o c/w on standard jedec 51-7 (4 layers, 2s2p) thermal test board. the maximum power dissipation at t a = 25 o c can be calculated by following formula: p d(max) = (125 o c - 25 o c) / 75 o c/w = 1.33w the thermal resistance r thja of esop-8 (exposed pad) is determined by the package design and the pcb design. however, the package design has been decided. if possible, it's useful to increase thermal performance by the pcb design. the thermal resistance can be decreased by adding copper under the expose pad of esop-8 package. we have to consider the copper couldn't stretch infinitely and avoid the tin overflow. place the input bypass capacitor as close as possible to the ape8977mp. a low esr capacitor larger than 470uf is recommended for the input capacitor. use short and wide traces to minimize parasitic resistance and inductance. inappropriate layout may result in large parasitic inductance and cause undesired oscillation between ape8977mp and the preceding powe converter.
advanced power electronics corp. ape8977mp typical performance characteristics 5 v in = 1.8v, v cntl = 3.3v, i out = 0a, source test v in = 1.8v, v cntl = 3.3v, i out = 10ma, source test i out = 0a, source test load transient (source test) load transient (sink test) v in = 5v, v cntl = 5v v in = 5v, v cntl = 5v v ref = 2.5v supplied by a regulator v ref = 2.5v supplied by a regulator i out = 0a, source test v in v out i out v in v out i out output voltage vs. temperature 0.7 0.8 0.9 1 1.1 -50 -25 0 25 50 75 100 125 temperature ( o c) output voltage (v) shutdown threshold vs. temperature 0.25 0.3 0.35 0.4 0.45 0.5 0.55 -50 -25 0 25 50 75 100 125 temperature ( o c) shutdown threshold (v) turn on turn off v in current vs. temperature 6 7 8 9 10 11 12 13 14 15 16 -50 -25 0 25 50 75 100 125 temperature ( o c) vin current (ua) v cntl current vs. temperature 1.5 2 2.5 3 3.5 4 -50 -25 0 25 50 75 100 125 temperature ( o c) vcntl current (ma) v in =1.8v, v cntl =5v v in =1.8v, v cntl =5v v in =1.8v, v cntl =3.3v v in =1.5v, v cntl =5v v in =1.5v, v cntl =3.3v v in =1.8v, v cntl =3.3v
advanced power electronics corp. ape8977mp typical performance characteristics 6 source current limit vs. temperature 4 4.5 5 5.5 -50 -25 0 25 50 75 100 125 temperature ( o c) source current limit (a) sink current limit vs. temperature 3 3.5 4 4.5 5 5.5 -50 -25 0 25 50 75 100 125 temperature ( o c) sink current limit (a) v in =1.8v, v cntl =3.3v v in =1.8v, v cntl =5v v in =1.8v, v cntl =3.3v v in =1.8v, v cntl =5v
advanced power electronics corp. ape8977mp marking information esop-8 7 8977mp ywwsss part number date code (ywwsss) y last digit of the year ww week sss se q uence package code
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