ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 1 g9612 global mixed-mode technology inc. low-dropout, 500ma linear regulator with reset features ? 500ma output current, with foldback current limiting ? high ripple rejection ? 1.5% output accuracy ? 2% reset threshold accuracy ? externally programmable reset time delay generator ? internal 500ma p-channel pass transistor ? 320a quiescent current ? thermal overload protection ? sot89-5 package applications ? cd rom or dvd rom ? slim-type cd/dvd ? dvd player general description the g9612 are low-dropout, linear regulator with reset function supply 3.4v, 3.3v or 2.5v output for currents up to 500ma. they are available in a 1.0w sot 89-5 package with 0.18 inch 2 copper heat sink. typical dropouts are 560mv at 5v and 500ma. other features include foldback current limiting and thermal overload protection. the reset function in g9612 detect v cc level with hysteresis, keeping it asserted for time delay deter- mined by external capacitor. the reset output is ac- tive low open-drain output. the detection threshold are 3.9v or 4.2v. the output is preset at 3.4v for the g9612a, 3.3v for the g9612b/c, and 2.5v for g9612d. the reset threshold is preset at 4.2v for g9612 a/b/d and 3.9v for g9612c. ordering information part number marking regulator output voltage reset threshold voltage temo. range pin- package g9612ateu g9612a 3.4 4.2 -40c to +85c sot89-5l g9612bteu g9612b 3.3 4.2 -40c to +85c sot89-5l G9612CTEU g9612c 3.3 3.9 -40c to +85c sot89-5l g9612dteu g9612d 2.5 4.2 -40c to +85c sot89-5l pin configuration typical operation circuit v in reset c d gnd g9612 output voltage v out 10f (tantalum or aluminum) 10k ? v cc r pull-high 1f reset v out v in sot 89-5l g9612 1 23 5 4 gnd c d v in reset c d gnd g9612 output voltage v out 10f (tantalum or aluminum) 10k ? v cc r pull-high 1f reset v out v in sot 89-5l g9612 1 23 5 4 gnd c d reset v out v in sot 89-5l g9612 1 23 5 4 gnd c d
ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 2 g9612 global mixed-mode technology inc. absolute maximum ratings supply voltage (in or out to gnd)..?.+0.3v to +6.5v input voltage?.??.????????????+ 6.5v continuous power dissipation (t a = +25c)?...?0.7w minimum footprint ( ja )?..????????.178c/w with 400mil x 450mil heatsink copper..???..?.1.0w ja ?????????????????..?125c/w output short-circuit duration??.??..?..??1 min operating temperature range???.-40c to +85c junction temperature?????.???.??+160c storage temperature range?.?.?-65c to +160c lead temperature (soldering, 10sec)??...?+300c stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. these are stress rat- ings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational se ctions of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliab ility electrical characteristics v in =5v, c in =1f, c out =10f, t j =t a =25c (note3), unless otherwise noted. typical values for regulators are at v in =5v. parameter symbol conditions min typ max units input voltage v in 2.5 6.0 v g9612a 3.35 3.4 3.45 g9612b/c 3.25 3.3 3.35 output voltage (note 1) v out g9612d 2.45 2.5 2.55 v load regulation ? v ldr i out =1ma to 500ma, v in =v out +1v 8 17 mv line regulation ? v lnr (v out +0.5v) v in 6v, i out =25ma -8 0.3 8 mv g9612a/b/c 560 610 dropout voltage (note 2) ? v do i out =500ma g9612d 650 700 mv parameter tempco v out 40 ppm/c f=120hz, i out =30ma 70 ripple rejection psrr f=120hz, i out =300ma 65 db output noise e n 20hz to 100khz, i out =30ma~500ma. 320 v rms quiescent current i q 320 450 a v out v foldback 650 900 1200 ma foldback voltage v foldback 0.6 0.78 0.95 v thermal shutdown temperature t sd 160 c thermal shutdown hysteresis ? t sd 30 c g9612a/b/d 4.11 4.2 4.29 reset threshold v th- g9612c 3.81 3.9 3.99 v g9612a/b/d 150 reset threshold hysteresis v hys g9612c 130 mv reset threshold tempco 40 ppm/c c d delay pin threshold voltage v tcd v cc = 5v 3.5 3.9 4.3 v c d pin sink current i cd v cc =1.5v, v cd =0.5v 3 4.3 ma c d pin pullup resistance r d 100 200 400 k ? reset output current low i ol v cc =2.5v, v reset =0.4v 8 11.5 ma reset function operating voltage v op reset sink current>10a 0.7 0.85 v note 1: (v in -v out ) is limited to keep the product (i out x (v in - v out )) from exceeding the package power dissipation limits. note 2: dropout voltage is (v in - v out ) when v out falls to 100mv below its nominal value at v in = v out +1v. for example, the g9612 is tested by measuring the v out at v in = v out +1v, then v in is lowered until v out falls 100mv below the measured value. the difference (v in - v out ) is then measured and defined as ? v do . note 3: low duty pulse techniques are used during test to maintain junction temperature as close to ambient as possible.
ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 3 g9612 global mixed-mode technology inc. typical performance characteristics (v in =5v,c in =c out =10f, cont=v in , t j =25c, unless otherwise noted) cont pin vs. output load transient load transient line transient line transient line transient
ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 4 g9612 global mixed-mode technology inc. typical performance characteristics (continued) over current response short circuit response power supply rejection ratio power supply rejection ratio power supply rejection ratio power supply rejection ratio rl=100 cl=10f rl=22 cl=10f rl=11 cl=10f rl=6.6 cl=10f
ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 5 g9612 global mixed-mode technology inc. typical performance characteristics (continued) safe operating area 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 input-output voltage differential(v) load current(a) 400mil450mil heatsink safe operating area 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 inpout -output voltage differential(v) load current(a) minimum footprint
ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 6 g9612 global mixed-mode technology inc. pin description pin no. pin name pin function 1 v in regulator input. supply voltage can range from 2.5v to 6v. 2 gnd ground 3 v out regulator output. sources up to 500ma. 4 c d external programmable time delay is set by the capacitor connect to c d pin. 5 reset reset open-drain output remains low while v in is below the reset threshold, and for delay time set by c d after v in rises above the reset threshold. figure 1. functional diagram detailed description the g9612 are low-dropout, low-quiescent current linear regulators with reset function the regulator in g9612 supply 3.4v, 3.3v or 2.5v output for load cur- rents up to 500ma. the reset function detect v in. as illustrated in figure 1, they consist of a 1.24v refer- ence, error amplifier, mosfet driver, p-channel pass transistor, and internal feedback voltage divider, reset threshold comparator and time delay generator. the 1.24v bandgap reference is connected to the er- ror amplifier?s inverting input. the error amplifier com- pares this reference with the feedback voltage and amplifies the difference. the mosfet driver reads the error signal and applies the appropriate drive to the p-channel pass transistor. if the feedback voltage is lower than the reference, the pass transistor gate is pulled lower, allowing more current to pass and in- creasing the output voltage. if the feedback voltage is too high, the pass transistor gate is pulled up, allowing less current to pass to the output. additional blocks of linear regulator include a foldback current limiter, reverse current protection, and thermal sensor. the g9612 also offer reset function to detect the level of v in . they assert a reset signal whenever v in supply voltage declines below a preset threshold (v th ), keep- ing it asserted for time delay set by capacitor con- nected to c d pin, after v in has resen above the high reset threshold (v th + v hys ). the reset is an active low, open-drain output. internal p-channel pass transistor the g9612 feature a 500ma p-channel mosfet pass transistor. this provides several advantages over similar designs using pnp pass transistors, including longer battery life. the p-channel mosfet requires no base drive, which reduces quiescent current con- siderably. pnp based regulators waste considerable amounts of current in dropout when the pass transistor saturates. they also use high base-drive currents un- der large loads. the g9612 do not suffer from these problems and consume only 320a of quiescent cur- rent. v out 1.24v reference mosfet driver with foldback current limit r1 r2 thermal protection p c d r d v in gnd reset v out 1.24v reference mosfet driver with foldback current limit r1 r2 thermal protection p c d r d v in gnd reset
ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 7 g9612 global mixed-mode technology inc. foldback current limiting the g9612 also include a foldback current limiter. it monitors and controls the pass transistor?s gate volt- age, estimating the output current and limiting it to 900ma for output voltages above 0.78v. if the output voltage drops below 0.78v, implying a short-circuit condition, the output current is limited to 400ma. thermal overload protection thermal overload protection limits total power dissipa- tion in the g9612. when the junction temperature ex- ceeds t j = +160c, the thermal sensor sends a signal to the shutdown logic, turning off the pass transistor and allowing the ic to cool. the thermal sensor will turn the pass transistor on again after the ic?s junction temperature cools by 30c, resulting in a pulsed out- put during thermal overload conditions. thermal overload protection is designed to protect the g9612 in the event of fault conditions. for continual operation, the absolute maximum junction temperature rating of t j = +160c should not be exceeded. operating region and power dissipation maximum power dissipation of the g9612 depends on the thermal resistance of the case and circuit board, the temperature difference between the die junction and ambient air, and the rate of air flow. the power dissipation across the device is p = i out (v in -v out ). the resulting maximum power dissipation is: (t j -t a ) p max = ( jc + ca ) where (t j -t a ) is the temperature difference between the g9612 die junction and the surrounding air, jc is the thermal resistance of the package chosen, and ca is the thermal resistance through the printed circuit board, copper traces and other materials to the sur- rounding air. the thermal resistance of sot89-5 with 0.18 inch 2 copper heat sink is ja = 125c/w. the power dissipation of g9612 is: p d = (v in - v out ) x i out the worst-case thermal resistance from junction to air ( ja ) requirements are: (150c -t a ) ja = p d use larger copper pad area to obtain specific heat sink thermal resistance values for larger output current, higher input-output difference, and higher ambient temperature. c d capacitor selection the reset timeout delay is set by internally pull-up r d (typical value 200k ? ) and external c d . when the voltage at c d pin exceeds the buffer thresh- old, typically 0.85 v cc , the reset output high. the voltage detector and buffer have built-in hysterisis to prevent erratic reset operation. for c d = 0.1f, typical reset time delay is 10ms. regulator output capacitor selection and regula- tor stability normally, use capacitors 0.1f minimum on the input and 10f minimum on the output of the g9612. the larger input capacitor values provide better supply noise rejection and line-transient response. improve load tran- sient response, stability, and power-supply rejection by using large output capacitors. for stable operation over the full temperature range and with load current up to 500ma, 10f tantalum or 47f aluminum minimum is recommended. too small capacitors with small esr can result in oscillation. transient considerations the typical operating characteristics show the g9612 load-transient response. two components of the output response can be observed on the load-transient graphs?a dc shift from the output im- pedance due to the different load currents, and the transient response. typical transients for step changes in the load current from 5ma to 500ma are 0.1v. increasing the output capacitor?s value attenu- ates transient spikes.
ver: 1.2 feb 13, 2003 tel: 886-3-5788833 http://www.gmt.com.tw 8 g9612 global mixed-mode technology inc. package information dimension in mm dimension in inch symbol min. max. min. max. a 4.40 4.60 0.173 0.181 b 4.05 4.25 0.159 0.167 c 1.50 1.70 0.059 0.067 d 1.30 1.50 0.051 0.059 e 2.40 2.60 0.094 0.102 f 0.80 ----- 0. 031 ----- g 3.00 ref 0.118 ref h 1.50 ref 0.059 ref i 0.40 0.52 0.016 0.020 j 1.40 1.60 0.055 0.063 k 0.35 0.41 0.014 0.016 l 5o typ 5o typ taping specification gmt inc. does not assume any res ponsibility for use of any circuitry described, no circuit patent licenses are implied and gmt inc. reserves the right at any t ime without notice to change said circuitry and specifications. l k j i h g b e f d c a l k j i h g b e f d c a feed direction sot 89-5l package orientation feed direction sot 89-5l package orientation
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