1.2v shunt regulator features applications trimmed 0.5% tolerance battery powered systems wide operating current range 60 m m a to 100ma switching power supplies low reference input current 0.4 m m a adjustable power supplies low dynamic output impedance telecommunications low output noise error amplifiers nominal temperature range to 85 c notebook/personal computer temperature-compensated: 60ppm/ c monitors/ vcr/ tv pagers general description the ams431l is a three-terminal adjustable shunt regulator with guaranteed temperature stability over the entire range of operation. the output voltage can be set to any value between 1.24v (v ref ) and 20v by adding two external resistors. the ams431l features 0.5% initial tolerance, low dynamic output impedance and operates over a wide current range. due to the sharp turn-on characteristics this device is an excellent replacement for zener diodes in many applications. ams431 is available in to-92, sot-89, 3 pin sot-23 and 5 pin sot-23 packages. ordering information: tol. package type operating to-92 sot-89 3 lead sot-23 5 lead sot-23 temp. range 0.5% ams431lan ams431lal ams431lam AMS431LAM1 -40 to +85 c 1.0% ams431lbn ams431lbl ams431lbm ams431lbm1 -40 to +85 c 2.0% ams431lcn ams431lcl ams431lcm ams431lcm1 -40 to +85 c pin connections to-92 sot-89 3l sot-23 5l sot-23 plastic package (n) (l) (m) (m1) 1 2 3 ref anode cathode 1 2 3 cathode anode ref cathode ref anode n/c anode cathode reference n/c 1 2 5 3 4 bottom view top view top view top view ams431l advanced monolithic systems http://www.ams-semitech.com 1
absolute maximum ratings (note 1) cathode voltage (v z ) 20v internal power dissipation (p d ) continuous cathode current (i z ) 100ma to-92 package 0.78w reference input current (i ref ) 3ma sot-89 package 0.91w junction temperature (t j ) -40 c to +125 c sot-23-3 package 0.28w sot-23-5 package 0.3 w storage temperature -65 c to +150 c thermal resistance ( q ja ) lead temperature (soldering, 10sec.) 265 c to-92 package 160 c/w sot-89 package 110 c/w sot-23-3 package 410 c/w sot-23-5 package 410 c/w note 1 : absolute maximum ratings indicate limits beyond which damage to the device may occur. operating ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. for guaranteed specifications and test conditions, see the electrical characteristics . the guaranteed specifications apply only for the test conditions listed. electrical characteristics electrical characteristics at i z =10 ma and t a = +25c unless otherwise noted. parameter conditions ams431la min typ max ams431lb min typ max ams431lc min typ max units reference voltage 1.234 1.240 1.246 1.228 1.240 1.252 1.215 1.240 1.265 v deviation of reference input voltage over temperature v z = v ref (circuit 1) t a = -40 c to +85 c 10 25 10 25 10 35 mv ratio of change in reference voltage to cathode voltage i z = 10ma d v = from v ref -0.5 -2.7 -0.5 -2.7 -0.5 -2.7 mv/v reference input current r1 =10k w , r2 = w (test circuit 2) 0.15 0.5 0.15 0.5 0.15 0.5 m a reference input current deviation over temperature r1 =10k w , r2 = w t a = full range (test circuit 2) 0.1 0.4 0.1 0.4 0.1 0.4 m a off state cathode current v z = 6v, v ref = 0v ( test circuit 3) 0.04 0.1 0.04 0.1 0.04 0.1 m a dynamic output impedance f < 1khz, v z = v ref i z =100 m a to 100ma (test circuit 1) 0.25 0.4 0.25 0.4 0.25 0.4 w minimum operating current v z = v ref (test circuit 1) 60 80 60 80 60 80 m a recommended operating conditions: min max cathode voltage, (v z ) v ref 20 v cathode current, (i z ) 80 m a 100ma ams431l advanced monolithic systems http://www.ams-semitech.com 2
test circuits v in i ref i z v z = v ref v ref v in v z i z v ref i ref r1 r2 v in v z i z off figure 1. test circuit for v z =v ref figure 2. test circuit for v ref vs i z . test circuit for i ref . figure 3. test circuit for off-state current typical applications 1) set the v out according to the following equation: 2) choose the value of r as follows: the maximum limit for r should be such that the cathode current, i z is greater than the minimum operating current (80 m a) at v in( min) . the minimum limit for r should b such that i z does not exceed 100ma under all load conditions, and the instantaneous turn-on value for i z does not exceed 150ma. both of the following conditions must be met: r2 r1 v in gnd v ref v out r1 i r2 r1 1 v v ref ref out + ? ? ? ? + = ( ) z in(max) min i on - turn ous instantane limit to 150ma v r 3 ( ) conditions operating normal under i limit to 100ma i v - v r z out(min) out in(max) min + 3 ams431l advanced monolithic systems http://www.ams-semitech.com 3
typical performance characteristics 0.01 1 10 100 10 100 1000 100000 reference impedance vs. frequency 0.1 reference impedance ( w ) 1 frequency (khz) -1 -0.5 0 0.5 1 -300 200 -100 cathode current vs. cathode voltage 1.5 cathode voltage (v) cathode current ( m a) -200 300 0 t a =25 c v r = v ref 100 -1.5 -1 0 0.5 1 -150 100 -50 cathode current vs. cathode voltage 1.5 cathode voltage (v) cathode current ( m a) -100 150 0 t a =25 c v r = v ref 50 -0.5 -50 25 50 75 100 125 1.248 1.242 150 reference voltage (v) reference voltage vs. junction temperature junction temperature ( c) 1.244 1.238 1.236 -25 0 i z = 100 m a 1.246 1.240 1.234 -50 25 50 75 100 125 150 100 150 reference input current vs. junction temperature junction temperature ( c) 125 75 -25 0 i z = 10 m a 50 -50 25 50 75 100 125 1.2 0.7 150 ratio of delta reference voltage to delta cathode voltage vs. junction temperature junction temperature ( c) 0.9 0.3 0.2 -25 0 i z = 10 m a 1.0 0.5 0.0 -50 25 50 75 100 125 250 150 150 off state cathode current vs. junction temperature junction temperature ( c) 50 -25 0 v r = 16v 200 100 0 reference input current ( na) r 1 = 10 k w r 2 = 1.1 0.8 0.6 0.4 0.1 v ref = 0v v z = 6v cathode current(off state) (na) d v z = 16v to v ref d v ref / d v z (- m v/v) -50 25 50 75 100 125 0.50 0.30 150 reference impedance vs. junction temperature junction temperature ( c) 0.10 -25 0 i z = 0.1 to 100ma 0.40 0.20 0 v z = v ref reference impedance ( w ) f< 1khz 0.45 0.35 0.25 0.15 0.05 i r = 60 m a t a =25 c ams431l advanced monolithic systems http://www.ams-semitech.com 4
typical performance characteristics (continued) 0.0 1.0 2.0 3.0 3.5 0.01 0.1 1 stability boundary condition 2.5 cathode current (ma) 0.001 load capacitance ( m f) 1.5 0.5 10 r2 r1 i z c l + - stability circuit t a =25 c v z = v ref v z = 2v stable stable -20 10 40 70 80 1k 10k 100k 1000k small signal gain and phase shift vs. frequency -10 50 small signal gain (db) 100 frequency (hz) 20 60 30 0 -180 -225 -270 -315 -360 phase shift (deg) 8.25k 15k i z 10 m f + - small signal gain and phase shift test circuit 232 out gnd ams431l advanced monolithic systems http://www.ams-semitech.com 5
package dimensions inches (millimeters) unless otherwise noted. 3l to-92 plastic package (n) 5 lead sot-23 plastic package (m1) 0.1400.010 (3.5560.127) 0.0600.010 (1.5240.254) 0.0150.002 (0.3810.051) 0.0160.003 (0.4060.076) 0.0500.005 (1.2700.127) 0.0600.005 (1.5240.127) dia 0.1800.005 (4.5720.127) 0.1800.005 (4.5720.127) 0.050 (1.270) max 0.500 (12.70) min uncontrolled lead dimensions 10 nom 5 nom n (to-92 ) ams drw# 042391 0.90 (2.286) nom 0.059-0.070 (1.50-1.75) 0.014-0.020 (0.350-0.50) 0.110-0.120 (2.794-3.048) 0.102-0.118 (2.60-3.00) 0.037 (0.95) typ 0.075 (1.90) typ 0.018-0.024 (0.457-0.610) 10 nom 0.0035-0.0080 (0.090-0.20) (sot-23-5 ) ams drw# 051001 0.036-0.051 (0.090-1.30) 0.003 (0.150) max 0.018-0.024 (0.457-0.610) 10 nom ams431l advanced monolithic systems http://www.ams-semitech.com 6
package dimensions inches (millimeters) unless otherwise noted (continued). 3 lead sot-23 plastic package (m) sot-89 plastic package (l) 0.047-0.055 (1.194-1.397) 0.015-0.017 (0.381-0.432) 0.110-0.120 (2.794-3.048) 0.083-0.098 (2.108-2.489) 0.035-0.040 (0.889-1.016) 0.070-0.080 (1.778-2.032) 0.018-0.024 (0.457-0.610) 10 nom 0.0034-0.0050 (0.086-0.127) (sot-23 ) ams drw# 051991 0.035-0.041 (0.089-1.041) 0.0005-0.0040 (0.013-0.102) 0.018-0.024 (0.457-0.610) 10 nom 0.090-0.102 (2.29-2.60) 0.173-0.181 (4.40-4.60) 0.064-0.072 (1.62-1.83) 0.155-0.167 (3.94-4.25) 0.059 (1.50) bsc 0.035-0.047 (0.89-1.20) l (sot-89 ) ams drw# 042392 0.118 (3.00) bsc 0.014-0.019 (0.36-0.48) 0.017-0.022 (0.44-0.56) 0.084-0.090 (2.13-2.29) 0.055-0.063 (1.40-1.60) 0.014-0.017 (0.35-0.44) ams431l advanced monolithic systems http://www.ams-semitech.com 7
|
