ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 1 G914X global mixed-mode technology inc. 150ma low-noise ldo regulators features ? ultra low output noise ? ? ? ? 30v (rms) ? ultra low 55a no-load supply current ? ultra low dropout 70mv @ 50ma load ? guarantee 150ma output current ? over-temperature and short-circuit protection ? fixed: 2.70v (g914a), 2.80v (g914b) 3.00v (g914c), 3.30v (g914d) 2.50v (g914e), 2.85v (g914f) 1.50v(g914g), 1.80v(g914h) ? max. supply current in shutdown mode < 1a ? stable with low cost ceramic capacitors applications ? notebook computers ? cellular phones ? pda ? hand-held devices ? battery-powered application general description the G914X is a low supply current, low dropout linear regulator that comes in a space saving sot23-5 package. the supply current at no-load is 55a. in the shutdown mode, the maximum supply current is less than 1a. operating voltage range of the G914X is from 2.5v to 5.5v. the over-current protection limit is set at 350ma typical and 200ma minimum. an over-temperature protection circuit is built-in in the G914X to prevent thermal overload. these power saving features make the G914X ideal for use in the battery-powered applications such as notebook com- puters, cellular phones, and pda?s. ordering information part marking voltage temp. range pin- package g914a 4axx 2.70v -40c~ +85c sot 23-5 g914b 4bxx 2.80v -40c~ +85c sot 23-5 g914c 4cxx 3.00v -40c~ +85c sot 23-5 g914d 4dxx 3.30v -40c~ +85c sot 23-5 g914e 4exx 2.50v -40c~ +85c sot 23-5 g914f 4fxx 2.85v -40c~ +85c sot 23-5 g914g 4gxx 1.50v -40c~ +85c sot 23-5 g914h 4hxx 1.80v -40c~ +85c sot 23-5 pin configuration typical operating circuit out byp sot23-5 G914X 5 4 1 in 2 3 gnd shdn in out gnd shdn G914X c in 1f _ battery output voltage c out 1 f fixed mode byp c byp 10nf out byp sot23-5 G914X 5 4 1 in 2 3 gnd shdn in out gnd shdn G914X c in 1f _ battery output voltage c out 1 f fixed mode byp c byp 10nf
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 2 G914X global mixed-mode technology inc. absolute maximum ratings v in to gnd??..??????..?.?.???-0.3v to +7v output short-circuit duration.?..?.??..??.?.infinite all other pins to gnd???.???.-0.3v to (v in + 0.3v) continuous power dissipation (t a = +25c) sot23-5 ??????????..????...?..520 mw operating temperature range?.?..... -40c to +85c junction temperature??????...??.??+150c ja (1) ?....??????.??????..?..240c/watt storage temperature range????.-65c to +160c lead temperature (soldering, 10sec)?.?.??+300c note (1): see recommended minimum footprint (figure 2) 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 =v out(std) +1v, v shdn =v in , t a =t j =25c, unless otherwise noted.) (note 1) parameter symbol conditions min typ max units input voltage (note 2) v in note2 5.5 v variation from specified v out , i out =1ma,v out 2.5v version -2 2 for g914h, i out =1ma -3 3 output voltage accuracy v out for g914g, i out =1ma -4 4 % maximum output current 300 ma current limit (note 3) i lim 350 ma i load = 0ma 55 120 ground pin current i q v in =3.6v i load = 50ma 145 a i out = 1ma 2 i out = 50ma, v out 2.7v version 70 mv v o (nom) 3.0v 230 300 2.5v v o (nom) 2.85v 250 330 v o (nom) = 1.8v 380 480 dropout voltage (note 4) v drop i out = 150ma v o (nom) = 1.5v 510 610 mv line regulation ? v lnr v in =v out +100mv to 5.5v, i out = 1ma 0.1 0.28 %/v load regulation (note 5) ? v ldr i out = 0ma to 150ma 1 % power supply rejection ratio psrr i out = 30ma c byp = 10nf, f = 120hz 57 db output voltage temperature coefficient v o / t i out = 50ma, t j = 25c to 125c 30 ppm/c c out = 1f, i out = 150ma, c byp =1nf 52 c out = 1f, i out = 150ma, c byp =10nf 35 c out = 1f, i out = 150ma, c byp = 100nf 30 output voltage noise (10hz to 100khz) (g914h) e n v in =v out +1v c out = 1f, i out = 1ma, c byp = 10nf 26 v rms shutdown v ih regulator enabled v in - 0.7 shdn input threshold v il regulator shutdown 0.4 v shdn input bias current i shdn v shdn = v in t a = +25c 0.003 0.1 shutdown supply current i q shdn v out = 0v t a = +25c 1 a thermal protection thermal shutdown temperature t shdn 150 c thermal shutdown hysteresis ? t shdn 15 c note 1: limits is 100% production tested at t a = +25c. low duty pulse techniques are used during test to maintain junction temperature as close to ambient as possible. note 2: v in (min) =v out (std) +v dropout note 3: not tested. for design purposes, the current limit should be considered 150ma minimum to 420ma maximum. note 4: the dropout voltage is defined as (v in - v out ) when v out is 100mv below the value of v out for v in = v out +1v. the performance of every G914X version, see ?typical performance characteristics?. note 5: regulation is measured at constant junction temperature using low duty cycle pulse testing. parts are tested for load regulation in the load range from 0ma to 150ma. changes in output due to heating effects are cov- ered by the thermal regulation specification.
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 3 G914X global mixed-mode technology inc. typical performance characteristics (v in = v o(std) +1v, v shdn = v in , c in =1f, c out =1f, g914d, t a =25c, unless otherwise noted.) dropout voltage vs. loading by G914X ouptut noise 10hz to 100khz output voltage vs. load current ground current vs. load current output voltage vs. input voltage supply current vs. input voltage 0 10 20 30 40 50 60 70 80 90 100 110 120 130 01234567 input voltage (v) supply current (a) iload=50ma iload=0a 0 50 100 150 200 250 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 load current (ma) ground current (a) 3.240 3.250 3.260 3.270 3.280 3.290 3.300 3.310 3.320 3.330 3.340 0 102030405060708090100110120130140150 load current (ma) output voltage (v) 0 100 200 300 400 500 600 700 800 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 loading (ma) dropout voltage (mv) t a =25c g914g g914h g914e g914a g914b g914f g914c g914d 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0123456 input voltage (v) output voltage (v) no load
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 4 G914X global mixed-mode technology inc. typical performance characteristics (continued) output noise vs. bypass capacitance output noise vs. load current line transient load transient load transient power supply rejection ripple 0 10 20 30 40 50 60 70 0.001 0.01 0.1 bypass capacitance (f) output noise (vrms) g914h v in =2.8v t a =25c c out =1f 0 10 20 30 40 50 60 70 1 10 100 1000 load current (ma) output noise (vrms) g914h v in =2.8v t a =25c c out =1f 0 10 20 30 40 50 60 70 80 0.1 1 10 100 frequency(khz) power supply rejection ratio(db) g914f v in =5v +2v(p-p) rl=100 cbyp=10nf
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 5 G914X global mixed-mode technology inc. typical performance characteristics (continued) turn on response time turn off response time turn-on time vs. bypass capacitance turn-off time vs. bypass capacitance shutdown pin delay shutdown response time 1 10 100 1000 10000 100000 0.1 1 10 100 bypass capactor (nf) time (s) prop delay rise time g914d i load =150ma c in =c out =1f 1 10 100 1000 0.1 1 10 100 bypass capacitor (nf) time (s) prop delay fall time g914d i load =150ma c in =c out =1f
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 6 G914X global mixed-mode technology inc. typical performance characteristics (continued) dropout voltage vs. temperature shdn input bias current vs. temperature ground current vs. temperature shutdown supply current vs. temperature -0.2 -0.1 0 0.1 0.2 -40-30-20-10 0 102030405060708090100110120130 junction temperature t j (c) shdn input bias current (a) g914d v in =4.3v -1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 -40-30-20-10 0 102030405060708090100110120130 junction temperature t j (c) shutdown supply current (a) g914d v in =4.3v 3.28 3.29 3.3 3.31 3.32 3.33 3.34 -40-30-20-10 0 102030405060708090100110120130 junction temperature t j (c) output voltage (v) g914d i load =1ma v in =5.5v v in =4.3v v in =3.4v 0 50 100 150 200 250 300 350 400 -40-30-20-100 102030405060708090100110120130 junction temperature t j (c) dropout voltage (mv) g914d i load =150ma i load =50ma i load =0ma 0 20 40 60 80 100 -40-30-20-10 0 102030405060708090100110120130 junction temperature t j (c) ground current (a) g914d v in =4.3v i out =0a output voltage vs. temperature
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 7 G914X global mixed-mode technology inc. pin description pin name function 1 in regulator input. supply voltage can range from +2.5v to +5.5v. bypass with 1f to gnd. 2 gnd ground. this pin also functions as a heatsink. solder to large pads or the circuit board ground plane to maximize thermal dissipation. 3 shdn active-high enable input. a logic low reduces the supply current to less than 1a. c onnect to in for normal operation. 4 byp this is a reference bypass pin. it should connect external 10nf capacitor to gnd to reduce out- put noise. bypass capacitor must be no less than 1nf. (c byp 1nf) 5 out regulator output. sources up to 150ma. bypass with a 1f, 0.2 ? typical esr capacitor to gnd. detailed description the block diagram of the G914X is shown in figure 1. it consists of an error amplifier, 1.25v bandgap refer- ence, pmos output transistor, internal feedback volt- age divider, shutdown logic, over current protection circuit, and over temperature protection circuit. the internal feedback voltage divider?s central tap is connected to the non-inverting input of the error ampli- fier. the error amplifier compares non-inverting input with the 1.25v bandgap reference. if the feedback voltage is higher than 1.25v, the error amplifier?s out- put becomes higher so that the pmos output transis- tor has a smaller gate-to-source voltage (v gs ). this reduces the current carrying capability of the pmos output transistor, as a result the output voltage de- creases until the feedback voltage is equal to 1.25v. similarly, when the feedback voltage is less than 1.25v, the error amplifier causes the output pmos to conduct more current to pull the feedback voltage up to 1.25v. thus, through this feedback action, the error amplifier, output pmos, and the voltage divider effec- tively form a unity-gain amplifier with the feedback voltage force to be the same as the 1.25v bandgap reference. the output voltage, v out , is then given by the following equation: v out = 1.25 (1 + r1/r2). (1) alternatively, the relationship between r1 and r2 is given by: r1 = r2 (v out / 1.25 + 1). (2) for the output voltage versions of G914X, the output voltages are 2.7v for g914a, 2.8v for g914b, 3.0v for g914c, 3.3v for g914d, and 2.5v for g914e, 2.85v for g914f, 1.50v for g914g and 1.80v for g914h. figure 1. functional diagram shdn in out shutdown logic 1.25v vref error amp over current protect & dynamic feedback gnd r1 r2 over temp. protect byp c byp shdn in out shutdown logic 1.25v vref error amp over current protect & dynamic feedback gnd r1 r2 over temp. protect byp c byp
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 8 G914X global mixed-mode technology inc. over current protection the G914X use a current mirror to monitor the output current. a small portion of the pmos output transistor?s current is mirrored onto a resistor such that the voltage across this resistor is proportional to the output current. this voltage is compared against the 1.25v reference. once the output current exceeds the limit, the pmos output transistor is turned off. once the output transistor is turned off, the current monitoring voltage decreases to zero, and the output pmos is turned on again. if the over current condition persist, the over current protec- tion circuit will be triggered again. thus, when the output is shorted to ground, the output current will be alternat- ing between 0 and the over current limit. the typical over current limit of the G914X is set to 350ma. note that the input bypass capacitor of 1f must be used in this case to filter out the input voltage spike caused by the surge current due to the inductive effect of the package pin and the printed circuit board?s routing wire. otherwise, the actual voltage at the in pin may exceed the absolute maximum rating. over temperature protection to prevent abnormal temperature from occurring, the G914X has a built-in temperature monitoring circuit. when it detects the temperature is above 150 o c, the output transistor is turned off. when the ic is cooled down to below 135 o c, the output is turned on again. in this way, the G914X will be protected against abnor- mal junction temperature during operation. shutdown mode when the shdn pin is connected a logic low volt age, the G914X enters shutdown mode. all the analog cir- cuits are turned off completely, which reduces the cur- rent consumption to only the leakage current. the out- put is disconnected from the input. when the output has no load at all, the output voltage will be discharged to ground through the internal resistor voltage divider. operating region and power dissipation since the G914X is a linear regulator, its power dissi- pation is always given by p = i out (v in ? v out ). the maximum power dissipation is given by: p dmax = (t j ? t a )/ ja = (150-25) / 240 = 520mw where (t j ? t a ) is the temperature difference the G914X die and the ambient air, ja , is the thermal resistance of the chosen package to the ambient air. for surface mount device, heat sinking is accom- plished by using the heat spreading capabilities of the pc board and its copper traces. in the case of a sot23-5 package, the thermal resistance is typically 240 o c/watt. (see recommended minimum footprint) [figure 2]. refer to figure 3 is the G914X valid oper- ating region (safe operating area) & refer to figure 4 is maximum power dissipation of sot 23-5. the die attachment area of the G914X?s lead frame is connected to pin 2, which is the gnd pin. therefore, the gnd pin of G914X can carry away the heat of the G914X die very effectively. to improve the power dis- sipation, connect the gnd pin to ground using a large ground plane near the gnd pin. applications information capacitor selection and regulator stability normally, use a 1f capacitor on the input and a 1f capacitor on the output of the G914X. larger input ca- pacitor values and lower esr provide better sup- ply-noise rejection and transient response. a higher- value input capacitor (10f) may be necessary if large, fast transients are anticipated and the device is located several inches from the power source. for stable opera- tion over the full temperature range, with load currents up to 120ma, a minimum of 1f is recommended. power-supply rejection and operation from sources other than batteries the G914X is designed to deliver low dropout voltages and low quiescent currents in battery powered sys- tems. power-supply rejection is 57db at low frequen- cies as the frequency increases above 20khz; the output capacitor is the major contributor to the rejec- tion of power-supply noise. when operating from sources other than batteries, improve supply-noise rejection and transient response by increasing the values of the input and output ca- pacitors, and using passive filtering techniques. load transient considerations the G914X load-transient response graphs show two components of the output response: a dc shift of the output voltage due to the different load currents, and the transient response. typical overshoot for step changes in the load current from 0ma to 100ma is 12mv. increasing the output capacitor's value and decreasing its esr attenuates transient spikes. input-output (dropout) voltage a regulator's minimum input-output voltage differential (or dropout voltage) determines the lowest usable supply voltage. in battery-powered systems, this will determine the useful end-of-life battery voltage. be- cause the G914X use a p-channel mosfet pass transistor, their dropout voltage is a function of r ds(on) multiplied by the load current cause the G914X use a p-channel mosfet pass transistor, their dropout voltage is a function of r ds(on) multiplied by the load current.
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 9 G914X global mixed-mode technology inc. layout guide an input capacitance of ? 1f is required between the G914X input pin and ground (the amount of the ca- pacitance may be increased without limit), this ca- pacitor must be located a distance of not more than 1cm from the input and return to a clean analog ground. input capacitor can filter out the input voltage spike caused by the surge current due to the inductive effect of the package pin and the printed circuit board?s routing wire. otherwise, the actual voltage at the in pin may exceed the absolute maximum rating. the output capacitor also must be located a distance of not more than 1cm from output to a clean analog ground. because it can filter out the output spike caused by the surge current due to the inductive effect of the package pin and the printed circuit board?s routing wire. figure 5 is G914X pcb recommended layout. figure 4 safe operating area safe operating area [power dissipation limit] 0 50 100 150 200 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 input-output voltage differential v in -v out (v) output current (ma) ta=25 ta=55 ta=85 maximum recommended output current t a =25c,still air 1oz copper on sot-23-5 package mounted on recommended mimimum footprint (r ja=240c/w) maximum power dissipation of sot-23-5 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 25 35 45 55 65 75 85 95 105 115 125 amibent temperature t a ( c) power dissipation (w) still air 1oz copper on sot-23-5 package mounted on recommended mimimum footprint (r ja=240c/w) note : v in(max) <=5.5v figure 4 power dissipation vs. temperature figure 3 safe operating area figure 5. fixed mode *distance between pin & capacitor must no more than 1cm figure 2. recommended minimum footprint
ver: 1.1 sep 18, 2002 tel: 886-3-5788833 http://www.gmt.com.tw 10 G914X global mixed-mode technology inc. package information note: 1. package body sizes exclude mold flash protrusions or gate burrs 2. tolerance 0.1000 mm (4mil) unless otherwise specified 3. coplanarity: 0.1000mm 4. dimension l is measured in gage plane dimensions in millimeters symbols min nom max a 1.00 1.10 1.30 a1 0.00 ----- 0.10 a2 0.70 0.80 0.90 b 0.35 0.40 0.50 c 0.10 0.15 0.25 d 2.70 2.90 3.10 e 1.40 1.60 1.80 e ----- 1.90(typ) ----- e1 ----- 0.95 ----- h 2.60 2.80 3.00 l 0.37 ------ ----- 1 1o 5o 9o 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. e e d h 1 l c b a2 a1 a e1 e e d h 1 l c b a2 a1 a e1 feed direction sot23-5 package orientation feed direction sot23-5 package orientation
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