1 gm2950/gm2951 v 2 .00 preliminary information gm 2950/gm2951 100 ma, low drop out voltage regulators application s ? battery powered systems ? cordless telephones ? radio control systems ? portable/palm top/notebook computers ? portable consumer equipments ? portable instruments ? automotive electronics ? smps post regulator ? voltage reference typical application circuit description the gm2950 and gm2951 is a low power voltage regulator. this device is an excellent choice for use in battery powered application such as cordless telephone, radio contr ol systems, and portable computers. the gm2950/gm2951 features very low quiescent current (75a typ.) and very low drop output voltage (typ. 40mv at light load and 380mv at 100ma). this includes a tight initial tolerance of 0.5% typ., extremely good load a nd line regulation of 0.05% typ., and very low output temperature coefficient, making the gm2950/ gm2951 useful as a low power voltage reference. the gm2951 is available in 8 - pin plastic packages. the regulator output voltage may be pin - strapped for a - xx volt or programmed from 1.24 volt to 29 volts with external pair of resistors. the gm2950 is offered in 3 - pin to - 92 package compatible with other fixed regulator. features ? high accuracy output voltage ? guaranteed 100ma output ? very low quiescent current ? low dropout voltage ? extremely tight load and line regulation ? very low temperature coefficient ? needs only 1 f capacitor for stability ? error flag warns of output dropout ? logic - controlled electronic shutdown ? output programmable from 1.24v to 29v gm 2951 - x.x v out sense 1 c in v out v in shutdown n 100k 2 3 4 sd gnd 5 6 7 8 v in fb v tap error c out 3.3 f error output gnd gnd
2 gm 2950/gm2951 v 2 .00 gm 2950/gm2951 100 ma, low drop out voltage regulators marking information and pin configurations (top view) gm2950 - x.x to - 92 g: green product vv: output voltage codes (05: 5.0v, 12:12v) a: assembly/test site code y: year ww: week marking information and pin configurations (top view) gm2951 - x.x so8 g: green product vv: output voltage codes ( a: adj, 05: 5.0v, 12:12v) a: assembly/test site code y: year ww: week 8.v in 1. v out 2 . sense 3. sd 5. error 6. v tap 7. gnd 4. gnd v out 1 3 v in 2 gnd gm2950g vv ayww gm 2951 g vvayww
3 gm2950/gm2951 v 2 .00 preliminary information gm 2950/gm2951 100 ma, low drop out voltage regulators ordering information gm2950 - x.x ordering n u mber output voltage packa g e shipp ing gm2950 - 3.3t92bg 3.3v to - 92 1,000 units/esd bag gm2950 - 3.3t92rlg 3.3v to - 92 2,000 units/ammo pack (tape) gm2950 - 5.0t92bg 5.0v to - 92 1,000 units/esd bag gm2950 - 5.0t92rlg 5.0v to - 92 2,000 units/ammo pack (tape) gm2951 - x.x gm2951 - 3.3s8rg 3.3v so - 8 2, 500 units/tape & reel gm2951 - 5.0s8rg 5.0v so - 8 2,500 units/tape & reel
4 gm 2950/gm2951 v 2 .00 gm 2950/gm2951 100 ma, low drop out voltage regulators absolute maximum ratings parameter symbol ratings units v in pin voltage v in - 0.3 to + 30 v fb pin voltage v fb - 1.5 to + 30 v sd pin voltage v sd - 0.3 to + 30 v error pin voltage v err - 0.3 to + 30 v operating junction temperature range t j - 40 to +150 c storage temperature t stg - 65 to +150 c thermal resistance, junction to ambient (so8 package) ja 180 c /w thermal resistance, junction to ambient (so8 package) j c 45 c /w lead temperature 1.6mm (1/6 inch) from case for 5 seconds t lead 260 c esd rating (human body model) esd 2 kv
5 gm2950/gm2951 v 2 .00 preliminary information gm 2950/gm2951 100 ma, low drop out voltage regulators block diagram gm2950 - x.x block diagram gm295 1 - x.x block diagram * for fixed output voltage option only v in gnd 1.23v reference error amplifier v out 60k v in gnd 1.23v reference error amplifier v out error v tap sens e sd 60mv error detection comparator fb * 60k *
6 gm 2950/gm2951 v 2 .00 gm 2950/gm2951 100 ma, low drop out voltage regulators electrical characte ristics ( u nless otherwise noted , v in = v out + 1 v, i out = 100 a, c out = 1 f, and t j = 25 c ) parameter symbol test condition (note 1) m in t yp m ax u nit output voltage v out t j = 25 c 0.99v o typ v o typ 1.01 v o typ v - 25 c t j 85 c 0.985 v o typ v o typ 1.015 v o typ full operating temperature 0.98 v o typ v o typ 1.02 v o typ output voltage temperature coefficient (note 2) 50 150 ppm/ c line regulation l nr v out + 1 v v in 30v 0.04 0.2 % load regulation (note 3) ldr 100 a i out 100ma 0.1 0.3 % dropout vol tage (note 4) v d i out = 100 a 50 80 mv i out = 100ma 380 450 ground current i gnd i out = 100 a 75 120 a i out = 100ma 3 12 ma dropout ground current i dg v in = v out C 0.5 v , i out = 100 a 110 170 a current limit i cl v out = 0v 160 200 ma ther mal regulation t reg 0.05 0.2 %/w output noise, 10hz to 100khz c out = 1 f 430 v rms c out = 200 f 160 c out = 3 f (bypass = 0.01, pin 7 to pin 1, gm2951 - x.x only) 100 gm2951 - x.x only reference voltage v re f 1.21 1.235 1.26 v full operat ing temperature 1.185 1.285 feedback pin bias current i fb 20 40 na reference voltage temperature coefficient (note 2) 50 ppm/ c feedback pin bias current temperature coefficient 0.1 na/ c error comparameter output leakage current i lk v oh = 30v 0.01 1.0 a output low voltage v ol v in = 4.5 v , i out = 400 a 150 250 mv upper threshold voltage v thh note 6 40 60 mv lower threshold voltage v thl note 6 75 95 mv hysteresis v hys 15 mv
7 gm2950/gm2951 v 2 .00 preliminary information gm 2950/gm2951 100 ma, low drop out voltage regulators electrical characteristics (unless otherwise noted, v in = v out + 1 v, i out = 100 out = 1 j = 25 c ) parameter symbol test condition (note 1) m in t yp m ax u nit shutdown input input logic voltage low regulator on 0.7 v input logic voltage low regulator off 2 shutdown pin input current i sd v sd = 2.4v 30 50 sd = 30v 450 600 regulator output current in shutdown (note 7) v out = 5.0v 3 10 out < 5.0v 20 2.0v out < 3.3v 30 notes: 1. additional conditions for gm2951 series are the fb tied to v tap and v out tied to sense and v sd 0.8v 2. output or reference voltage temperature coefficients are defined as the worst case voltage change divided by the total temperature range. 3. the regulation is measured at a constant junction temperature using pulse testing with a low duty cycle. changes in the output voltage due to heating effects are covered under the specification for thermal regulation. 4. the dropout voltage is defined as the input - to - output differential, at which the output voltage drops 100mv below it nominal valu e measure at 1v differential. at very low values of programmed output voltage, the minimum input supply voltage (2v) (2.3v over temperature) must be taken into account. 5. v ref v out (v in - 1v), 2.3v v in 30v, 100 a i out 100ma, t j t jmax 6. comparator thresholds are expressed in terms of a volta g e differential at the fb terminal below the nominal reference voltage measure d at v out + 1v input. to express these thresholds in terms of an output voltage change, multiply by the error amplifier gain = v out /v ref = (r1 + r2)/r2. for examples, at a programmed output voltage of 5v, the error output is guaranteed to go lo w when the output drops by 95mv x 5v/1.235v = 384mv . thresholds remain constant as a percent of vout as vout is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% guaranteed. 7. v sd 2v, v in 30v, v out = 0, the fb pin is tied to v tap .
8 gm 2950/gm2951 v 2 .00 gm 2950/gm2951 100 ma, low drop out voltage regulators application notes ? external capacitors for better stability, it recommended to use a 1.0f or greater capacitor tied between v out and gnd. the esr of about 5 or less and resonant frequency above 50 0khz are important parameters in the value of capacitor. the capacitor value can be varied, at lower output current, less output capacitance is required. for the currents below 10ma, the value of capacitor can reduced to 0.33f, and 0.1f for 1ma. more ou tput capacitance is needed for gm2951 family at voltage below 5v since it runs the error amplifier at lower gain. at worst case, 3.3f or greater must be used for condition of 100ma load at 1.25v output. if gm2951 is connected to battery or between ac fil ter capacitor and input is 10 inches wire then 1f tantalum or aluminum electrolytic capacitor should be connected between v in and gnd. instability can occur if stray capacitor to fb terminal (pin 7). this could be eliminated by a 100pf capacitor between v out and fb pins and increasing output capacitor to 3.3f. ? reducing output noise to reduce the ac noise presented at v out pin s , one of the workable approaches is to reduce the regulator bandwidth by increasing the output capacitor value. however, this app roach is not relatively efficient. it is recommend ed to use a bypass capacitor across r1 sine it reduces the high frequency gain from 4 to unity. with the bypass capacitor, noise no longer scales with output voltage so the improvements are more efficient. ? programming the output voltage the gm2951 output voltage is programmable from 1.24v to 29v by external resistors shown in figure below . compared with fixed output voltage option, pin 2 and pin 6 are left open and the external resistors r1 and r2 set the v out by the formula: v out = v ref x (1 + r1/r2) where v ref is 1.235 v gm 2951 - a v out sense 1 c in see application note v out v in shutdown n 100k 2 3 4 sd gnd 5 6 7 8 v in fb v tap error c out 3.3 f error output gnd gnd c bypass 0.1 f r1 r2 v ref
9 gm2950/gm2951 v 2 .00 preliminary information gm 2950/gm2951 100 ma, low drop out voltage regulators package outline dimensions C to 92 package outline dimensions C so 8 3.85 C 4.19 4.7 C 5.2 4.9 C 5.2 12.7 C 14..2 1.22 C 1.32 0.4 C 0.55 typ. 0.189 C 0.197 ( 4.800 C 5.004 ) 0. 228 C 0. 244 ( 5.791 C 6.198 ) 0. 150 C 0. 157 ( 3.810 C 3.988 ) 0. 008 C 0. 010 ( 0.203 C 0.254 ) 0. 004 C 0. 010 ( 0. 10 2 C 0.254 ) 0. 053 C 0. 059 ( 1.346 C 1.753 ) 0. 014 C 0. 020 ( 0.356 C 0.508 ) 0. 016 C 0. 050 ( 0.406 C 0.270 ) 0. 05 0 ( 1.270 ) typ . seating plan 8.0 max
10 gm 2950/gm2951 v 2 .00 gm 2950/gm2951 100 ma, low drop out voltage regulators o rdering number g m 2 9 50 - 3 . 3 t92 b g a p m g a m m a m i c r o c i r c u i t t yp e o u t p u t v o l t a g e p a c k a g e t yp e s h i p p i n g t yp e 3 . 3 = 3 . 3 v 5 . 0 = 5 . 0 v t 9 2 : t o 9 2 s t 8 9 : s o t 8 9 s t 2 3 : s o t 2 3 b : b a g rl : ammo pack ( t ape) t : tube r: t ape & reel g : g r e e n o rdering number g m 2 951 - 2.2 s 8 r g a p m g a m m a m i c r o c i r c u i t t yp e o u t p u t v o l t a g e p a c k a g e t yp e s h i p p i n g t yp e a = a d j 3 . 3 = 3 . 3 v 5 . 0 = 5 . 0 v s 8 : s o 8 t : tube r: t ape & reel b l a n k : p b - f r e e g : g r e e n note: pb - free products : ? rohs compliant and compatible with the current require - ments of ipc/jedec j - std - 020. ? suitable for use in pb - free soldering processes with 100% matte tin (sn) plating. green produc ts : ? l ead - free (rohs compliant) ? h alogen free(br or cl does not exceed 900ppm by weight in homogeneous material and total of br and cl does not exceed 1500ppm by weight)
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