RT9181 general description the RT9181 is a low dropout voltage regulator with an output 2% accuracy and supply a continuous 150ma current within operating range from a +3v to +5.5v input. the power good function monitors the output voltage and indicates by pulling low the power good output (open drain). the RT9181 requires a small output capacitor with low esr for stabilizing output voltage. the device also minimizes output overshoot during power up. the RT9181 uses an internal pmos as the pass device, which consumes 160 a supply current independent of load and dropout conditions. the ce pin controls the output and consumes no input bias current. other features include current limiting, over temperature protection, and under voltage lockout. applications z processor power-up sequencing z laptop, notebook, and palmtop computers ordering information RT9181 ? ? features z low dropout voltage regulator, output 1.2v z up to 150ma output current z power good (pog) function z chip enable/shutdown function z load independent, low ground current, 160 a z current limiting and thermal protection z under voltage lockout (uvlo) z low variation due to load and line regulation z output stable with low esr capacitors z sot-25 package pin configurations part number pin configurations RT9181cb (plastic sot-25) top view 1. vin 2. gnd 3. ce 4. pog 5. vout typical application circuit operating temperature range c: commercial standard package type b : sot-25 54 3 2 1 vin ce gnd pog vout c in 1 f v in on off c ou t 1 f v out pog 10k 1 of 3 4008-318-123 sales@twtysemi.com http://www.twtysemi.com product specification
pin description pin name pin function vin input pin gnd power ground pin ce enable/shutdown input (active high) pog power good indicator vout output pin function block diagram + _ gate control verf undervoltage lockout current limit shutdown control thermal sensor output voltage detection delay timer power good control good fault vout pog gnd vin ce 2 of 3 4008-318-123 sales@twtysemi.com http://www.twtysemi.com RT9181 product specification
absolute maximum ratings z input voltage, v in 7v z ce input voltage 7v z power good output voltage 7v z power dissipation, p d @ t a = 25 c sot-25 570mw z junction temperature range -40 c ~ 125 c z storage temperature range -65 c ~ 150 c z operating temperature range 0 c ~ 70 c z lead temperature (soldering, 10 sec.) 260 c electrical characteristics (v in = 5v, c in = c out = 1 f, t a = 25 c, unless otherwise specified) parameter symbol test conditions min typ max units input voltage range v in 3--5.5v i l = 25ma 1.182 1.2 1.218 output voltage accuracy ? v out i l = 0.1ma, t a = 0 c to 70 c (note) -2 -- +2 % output load current continuous 150 -- -- ma current limit i limit r load = 1 ? 160 300 -- ma gnd current i g no load 90 160 250 a line regulation ? v line v in = 3 to 5.5v, i out = 0.1ma -0.3 -- +0.3 % load regulation ? v load i l = 0.1ma to 150ma -- -- +3 % dropout voltage v drop i l = 150ma -- 1 -- v ce input high threshold v in = 3 to 5.5v 2 -- -- v ce input low threshold v in = 3 to 5.5v -- -- 0.8 v ce input bias current ce = gnd or v in -- -- 100 na ce supply current ce = gnd -- 0.01 -- a v pogh power good low threshold output falls % of v out (power not timer ( power g ood )) 85 -- -- % v pogh power good high threshold output reaches % of v out , start dela y timer ( power g ood ) -- -- 90 % v ol power good output logic low fault condition, i ol = 100 a----0.4v td (pog) delay time to power good see timing diagram 1 2 5 ms power up overshoot maximum voltage overshoot allowed on output durin g power-up -- 1 -- % thermal shutdown temperature t sd -- 150 -- c thermal shutdown hysteresis -- 20 -- c output voltage ac psrr 100hz, c out = 1 f, r load = 100 ? -- 62 -- db note: assured by design, not tested in production 3 of 3 4008-318-123 sales@twtysemi.com http://www.twtysemi.com RT9181 product specification
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