advanced power electronics corp. ape8981 3a ultra low dropout linear regulator features description ultra low dropout 0.21v(typical) @ 2a output current for 1.2v output voltage low esr output capacitor (multi-layer chip capacitors (mlcc)) applicable en pull-low for ape8981mp-a en pull-high for ape8981mp-b fast transient response adjustable output voltage by external resistors power-on-reset monitoring on both vcntl and vin pins internal soft-start current-limit and thermal shutdown protection power-ok output with a delay time so-8 with exposed pad pb-free & dfn 3x3-10l package. halogen free product data and specifications subject to change without notice 201301046 typical application 1 the ape8981 series is a 3a ultra low dropout linea r 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 powe r dissipation and provide extremely low dropout. the ape8981 series 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 othe r converter for power sequence. the ape8981 series can be enabled by other powe r system. pulling and holding the en pin below 0.4v shuts of f the output. the ape8981 series is available in dfn 3x3-10l & esop-8 package which features small size as so-8 and an exposed pad to reduce the junction-to-case resistance. pok en vin vcntl nc vout fb gnd ape8981 u1 1uf c2 4.7uf c1 10k r3 20k r1 10k r2 10uf cout pok en *option cf v out v in v cntl .
advanced power electronics corp. ape8981 absolute maximum ratings (note1) cntl supply voltage (v cntl ) -------------------------- - -0.3v to 6.5v input supply voltage (v in ) ------------------------------ - -0.3v to 6.5v en & fb pin voltage (v en /v fb ) ------------------------ - -0.3v to vcntl+0.3v power good voltage (v pok ) --------------------------- - -0.3v to 6.5v power dissipation (p d ) --------------------------------- - 2.5w storage temperature range (t st ) ------------------- - -65c to 150c junction temperature range (t j ) -------------------- - -40c to 150c esop-8 ------ - 40c/w dfn 3x3-10l 62.5c/w thermal resistance junction to case (rth jc ) note esop-8 ------ - 15c/w dfn 3x3-10l 17c/w note. mounted on a demo board recommended operating conditions operating junction temperature range (t oj ) ---- - -40c to 125c operating ambient temperature range (t oa ) ---- - -40c to 85c vcntl supply voltage (v cntl ) ------------------------ - 3v to 6v input supply voltage (v in ) ------------------------------ - 1.1v to 5.5v output voltage (v out )@v cntl > v out + 2.5v ------ - 0.8v to 2.8v output cunrrent (i out ) ----------------------------------- - 0a to 3a package/ordering informatio n 2 thermal resistance junction to ambient (rth ja ) note ( top view ) 1 2 3 4 8 7 6 5 nc vout esop-8 gnd fb en pok vin vcntl gnd ( top view ) 1 2 3 4 8 7 6 dfn 3x3-10l gnd 5 9 10 vout vout vout fb pok en vin vin vin vcntl package type mp : esop-8 gn3 : dfn 3x3-10l ape8981x-x en function a : internal pull low b : internal pull high .
advanced power electronics corp. ape8981 electrical specifications v cntl = 5v, v in =1.8v, v out =1.2v, t a =25 o c unless otherwise specified parameter sym test condition min typ max units v in por threshold v in 0.8 0.9 1 v v in por hysteresis v in(hys) - 0.5 - v v cntl nominal supply current i cntl en= v cntl - 1.3 - ma ape8981mp-a - - 1 ape8981mp-b - 10 30 v cntl =3 ~ 6v, i out =10ma, v in =v out +0.5~5.5v load regulation i out =0a ~ 2a - 0.5 1 % i out =100ma, v cntl =v en =5.0v, v out =1.2v dropout voltage v drop i out = 2a, v cntl =5v, v out = 1.2v - 0.21 0.3 v v out pull low resistance en=0v - 40 - .
advanced power electronics corp. ape8981 pin descriptions pin symbol pin description pok power ok output pin ape8981mp-a: internal pull low; high for enable, low or floating for shutdown. ape8981mp-b: internal pull high; high or floating for enable, low for shutdown. vin power input pin of the control circuitry. the pin is monitored for power-on reset purpose. nc no connect vout output voltage fb feedback pin gnd gnd pin block diagram ape8981mp-a ape8981mp-b 4 en supply input for power conversion. the pin is monitored for power-on reset purpose. vcntl -+ vin vout gnd error amp en vcntl soft -start and control logic power- on reset current limit thermal shutdown bandgap fb -+ pok delay pok 94% v ref n-mosfet 10ua enable -+ vin vout gnd error amp en vcntl soft -start and control logic power- on reset current limit thermal shutdown bandgap fb -+ pok delay pok 94% v ref n-mosfet 10ua enable .
advanced power electronics corp. ape8981 pin description fb vin vcntl pok en vout function description power-on-reset internal soft-start output voltage regulation 5 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: 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 0.2ms. 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. 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 r1 in parallel to improve load transient response. the r2 range in 1k~4.7k .
advanced power electronics corp. ape8981 function description current-limit thermal shutdown application information capacitor selection 6 a thermal shutdown circuit limits the junction temperature of ape8981. when the junction temperature exceeds +160c, 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 40 c, resulting in a pulsed output during continuous thermal overload conditions. the thermal shutdown designed. normally, use a mlcc capacitor on the input and output of the ape8981. larger input capacitor values provide better supply-noise rejection and transient response. a higher- value output capacitor may be necessary if large, fast transients are anticipated and the device is located several inches from the power source. the x5r and x7r type in mlcc is recommended. for aluminum electrolytic capacitor application, 100uf in input capacitor and 220uf in output capacitor (30m .
advanced power electronics corp. ape8981 typical performance characteristics 7 load regulation line regulation dropout voltage at v cntl =5v dropout voltage at v cntl =3.3v i cntl vs. t j i cntl-sd (ape8981mp-b) vs. t j 0.780 0.785 0.790 0.795 0.800 0.805 0.810 0.815 0.820 3 3.4 3.8 4.2 4.6 5 v cntl (v) v o (v) io=0ma io=1a 0.75 0.76 0.77 0.78 0.79 0.80 0.81 0.82 0.83 0.84 0.85 0 0.5 1 1.5 2 2.5 3 i out (a) v o (v) vcntl=5 0 100 200 300 400 500 600 700 800 900 1000 0 0.5 1 1.5 2 2.5 3 i out (a) v drop (mv) vo=2.5v vo=1.8v vo=1.2v vo=1.05v 0 100 200 300 400 500 600 700 800 900 1000 0 0.5 1 1.5 2 2.5 3 i out (a) v drop (mv) vo=1.2v vo=1.05v 0.0 0.5 1.0 1.5 2.0 2.5 3.0 -40 -20 0 20 40 60 80 t j (c) i cntl (ma) 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 -40 -20 0 20 40 60 80 t j (c) i cntl-sd (ua) .
advanced power electronics corp. ape8981 typical performance characteristics v en v in v out v out pok pok i out =3a i out =3a v fb vs. t j v en vs. t j 8 en on with pok delay vin power ?on 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 -40 -20 0 20 40 60 80 t j (c) v en (v) venh venl 0.70 0.72 0.74 0.76 0.78 0.80 0.82 0.84 0.86 0.88 0.90 -40 -20 0 20 40 60 80 t j (c) v fb (v) .
advanced power electronics corp. ape8981 marking information esop-8 dfn 3x3-10l 9 part number date code (ywwsss) y .
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