View LT1990HS8PBF_4892920.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

lt1990 1 1990fb battery cell voltage monitoring high voltage current sensing signal acquisition in noisy environments input protection fault protected front ends level sensing isolation pin selectable gain of 1 or 10 high common mode voltage range: 85v window (v s = 5v, 0v) 250v (v s = 15v) common mode rejection ratio: 70db min input protection to 350v gain error: 0.28% max psrr: 82db min high input impedance: 2m ? differential, 500k ? common mode micropower: 120 a max supply current wide supply range: 2.7v to 36v 3db bandwidth: 100khz rail-to-rail output 8-pin so package 250v input range g = 1, 10, micropower, difference amplifier the lt 1990 is a micropower precision difference ampli- fier with a very high common mode input voltage range. it has pin selectable gains of 1 or 10. the lt1990 operates over a 250v common mode voltage range on a 15v supply. the inputs are fault protected from common mode voltage transients up to 350v and differential voltages up to 500v. the lt1990 is ideally suited for both high side and low side current or voltage monitoring. on a single 5v supply, the lt1990 has an adjustable 85v input range, 70db min cmrr and draws less than 120 a supply current. the rail-to-rail output maximizes the dy- namic range, especially important for single supplies as low as 2.7v. the lt1990 is specified for single 3v, 5v and 15v supplies over both commercial and industrial temperature ranges. the lt1990 is available in the 8-pin so package. full-bridge load current monitor r s +v source i l ?2v v cm 73v v out = v ref (10 ?i l ?r s ) + 40k 40k 100k 100k 900k 1m 1m 900k 10k 10k v out lt1990 lt6650 gnd in out fb 54.9k 20k 1nf 1 f v ref = 1.5v 1990 ta01 5v 7 2 3 4 1 8 6 5 + applicatio s u descriptio u features typical applicatio u , lt, ltc and ltm are registered trademarks of linear technology corporation. all other trademarks are the property of their respective owners.
lt1990 2 1990fb order options tape and reel: add #tr lead free: add #pbf lead free tape and reel: add #trpbf lead free part marking: http://www.linear.com/leadfree/ s8 part marking symbol parameter conditions min typ max units g gain pins 5 and 8 = open 1 pins 5 and 8 = v ref 10 ? g gain error v out = 0.5v to (+vs) ?.75v lt1990, g = 1 0.4 0.6 % lt1990a, g = 1 0.07 0.28 % g = 10, v s = 5v, 0v 0.2 0.8 % gnl gain nonlinearity v s = 5v, 0v; v out = 0.5v to 4.25v g = 1 0.001 0.005 % g = 10 0.01 % v cm input voltage range guaranteed by cmrr v s = 3v, 0v; v ref = 1.25v ? 25 v v s = 5v, 0v; v ref = 1.25v ? 80 v v s = 5v, 0v; v ref = 2.5v ?8 47 v cmrr common mode rejection ratio v s = 3v, 0v (note 7) rti (referred to input) v cm = ?v to 25v, v ref = 1.25v lt1990 60 68 db lt1990a 70 75 db v s = 5v, 0v v cm = ?v to 80v, v ref = 1.25v lt1990 60 68 db lt1990a 70 75 db v s = 5v, 0v (note 7) v cm = ?8v to 47v, v ref = 2.5v lt1990 60 68 db lt1990a 70 75 db total supply voltage (v + to v ) ............................... 36v input voltage range continuous ...................................................... 250v transient (0.1s) ............................................... 350v differential ....................................................... 500v output short-circuit duration (note 3) ............ indefinite operating temperature range (note 4) lt1990c .............................................. ?0 c to 85 c lt1990i ............................................... ?0 c to 85 c lt1990h ........................................... ?0 c to 125 c specified temperature range (note 5) lt1990c .............................................. ?0 c to 85 c lt1990i ............................................... ?0 c to 85 c lt1990h ........................................... ?0 c to 125 c junction temperature ........................................... 150 c storage temperature range .................. 65 c to 150 c lead temperature (soldering, 10 sec.)................. 300 c order part number 1990 1990i 1990h 1990a 1990ai 1990ah lt1990cs8 lt1990is8 lt1990hs8 lt1990acs8 lt1990ais8 lt1990ahs8 absolute axi u rati gs w ww u package/order i for atio uu w 3v/5v electrical characteristics v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, t a = 25 c, unless otherwise noted. (note 6) (notes 1, 2) consult ltc marketing for parts specified with wider operating temperature ranges. t jmax = 150 c, ja = 190 c/w top view gain1 v + out gain2 ref ?n +in v s8 package 8-lead plastic so 1 2 3 4 8 7 6 5
lt1990 3 1990fb 3v/5v electrical characteristics v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, t a = 25 c, unless otherwise noted. (note 6) symbol parameter conditions min typ max units v os offset voltage, rti g = 1, 10 0.8 3 mv e n input noise voltage, rti f o = 0.1hz to 10hz 22 v p-p noise voltage density, rti f o = 1khz 1 v/ hz r in input resistance differential 2 m ? common mode 0.5 m ? psrr power supply rejection ratio, rti v s = 2.7v to 12.7v, v cm = v ref = 1.25v 80 92 db minimum supply voltage guaranteed by psrr 2.4 2.7 v i s supply current (note 8) 105 120 a v ol output voltage swing low ?n = v + , +in = half supply (note 8) 30 50 mv v oh output voltage swing high ?n = 0v, +in = half supply v s = 3v, 0v, below v + 100 150 mv v s = 5v, 0v, below v + 120 175 mv i sc output short-circuit current short to gnd (note 9) 4 8 ma short to v + (note 9) 13 20 ma bw bandwidth (3db) g = 1 100 khz g = 10 6.5 khz sr slew rate g = 1, v s = 5v, 0v, v out = 0.5v to 4.5v 0.5 v/ s settling time to 0.01% 4v step, g = 1, v s = 5v, 0v 45 s av ref reference gain to output g = 1 1 0.0007 g = 10 1 0.007 the denotes the specifications which apply over the temperature range of 0 c t a 70 c. v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, unless otherwise noted. (notes 4, 6) lt1990c/lt1990i symbol parameter conditions min typ max units ? g gain error v out = 0.5v to (+v s ) ?0.75v lt1990, g = 1 0.65 % lt1990a, g = 1 0.33 % g = 10 0.90 % g/t gain vs temperature g = 1 (note 10) 2 10 ppm/ c g = 10 (note 10) 7 20 ppm/ c v cm input voltage range guaranteed by cmrr v s = 3v, 0v, v ref = 1.25v ? 25 v v s = 5v, 0v, v ref = 1.25v ? 80 v v s = 5v, 0v, v ref = 2.5v ?7 48 v cmrr common mode rejection ratio, rti v s = 3v, 0v (note 7) v cm = 5v to 25v, v ref = 1.25v lt1990 58 db lt1990a 68 db v s = 5v, 0v v cm = 5v to 80v, v ref = 1.25v lt1990 58 db lt1990a 68 db v s = 5v, 0v (note 7) v cm = 38v to 47v, v ref = 2.5v lt1990 58 db lt1990a 68 db
lt1990 4 1990fb 3v/5v electrical characteristics the denotes the specifications which apply over the temperature range of 0 c t a 70 c. v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, unless otherwise noted. (notes 4, 6) the denotes the specifications which apply over the temperature range of ?0 c t a 85 c. v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, unless otherwise noted. (notes 4, 6) lt1990c/lt1990i symbol parameter conditions min typ max units v os input offset voltage, rti v s = 3v, 0v g = 1, 10 4.1 mv v s = 5v, 0v g = 1, 10 4.1 mv v os /t input offset voltage drift, rti (note 10) 522 v/ c v osh input offset voltage hysteresis, rti (note 11) 230 v psrr power supply rejection ratio, rti v s = 2.7v to 12.7v v cm = v ref = 1.25v g = 1, 10 78 db minimum supply voltage guaranteed by psrr 2.7 v i s supply current (note 8) 150 a v ol output voltage swing low ?n = v + , +in = half supply (note 8) 60 mv v oh output voltage swing high ?n = 0v, +in = half supply v s = 3v, 0v, below v + 180 mv v s = 5v, 0v, below v + 205 mv i sc output short-circuit current short to gnd (note 9) 3ma short to v + (note 9) 11 ma lt1990c/lt1990i symbol parameter conditions min typ max units ? g gain error v out = 0.5v to (+v s ) ?0.75v lt1990, g = 1 0.67 % lt1990a, g = 1 0.35 % g = 10 0.95 % g/t gain vs temperature g = 1 (note 10) 2 10 ppm/ c g = 10 (note 10) 7 20 ppm/ c v cm input voltage range guaranteed by cmrr v s = 3v, 0v, v ref = 1.25v ? 25 v v s = 5v, 0v, v ref = 1.25v ? 80 v v s = 5v, 0v, v ref = 2.5v ?7 48 v cmrr common mode rejection ratio, rti v s = 3v, 0v (note 7) v cm = 5v to 25v, v ref = 1.25v lt1990 57 db lt1990a 67 db v s = 5v, 0v v cm = 5v to 80v, v ref = 1.25v lt1990 57 db lt1990a 67 db v s = 5v, 0v (note 7) v cm = 38v to 47v, v ref = 2.5v lt1990 57 db lt1990a 67 db
lt1990 5 1990fb lt1990h symbol parameter conditions min typ max units ? g gain error v out = 0.5v to (+v s ) ?0.75v lt1990, g = 1 0.69 % lt1990a, g = 1 0.37 % g = 10 0.97 % g/t gain vs temperature g = 1 (note 10) 2 10 ppm/ c g = 10 (note 10) 7 20 ppm/ c v cm input voltage range guaranteed by cmrr v s = 3v, 0v, v ref = 1.25v ? 25 v v s = 5v, 0v, v ref = 1.25v ? 80 v v s = 5v, 0v, v ref = 2.5v ?7 48 v cmrr common mode rejection ratio, rti v s = 3v, 0v (note 7) v cm = 5v to 25v, v ref = 1.25v lt1990 56 db lt1990a 66 db v s = 5v, 0v v cm = 5v to 80v, v ref = 1.25v lt1990 56 db lt1990a 66 db v s = 5v, 0v (note 7) v cm = 38v to 47v, v ref = 2.5v lt1990 56 db lt1990a 66 db 3v/5v electrical characteristics the denotes the specifications which apply over the temperature range of ?0 c t a 85 c. v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, unless otherwise noted. (notes 4, 6) lt1990c/lt1990i symbol parameter conditions min typ max units v os input offset voltage, rti v s = 3v, 0v g = 1, 10 4.5 mv v s = 5v, 0v g = 1, 10 4.5 mv v os /t input offset voltage drift, rti (note 10) 522 v/ c v osh input offset voltage hysteresis, rti (note 11) 230 v psrr power supply rejection ratio, rti v s = 2.7v to 12.7v v cm = v ref = 1.25v 76 db minimum supply voltage guaranteed by psrr 2.7 v i s supply current (note 8) 170 a v ol output voltage swing low ?n = v + , +in = half supply (note 8) 70 mv v oh output voltage swing high ?n = 0v, +in = half supply v s = 3v, 0v, below v + 200 mv v s = 5v, 0v, below v + 275 mv i sc output short-circuit current short to gnd (note 9) 2ma short to v + (note 9) 8ma the denotes the specifications which apply over the temperature range of ?0 c t a 125 c. v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, unless otherwise noted. (notes 4, 6) 3v/5v electrical characteristics
lt1990 6 1990fb 15v electrical characteristics v s = 15v, r l = 10k, v cm = v ref = 0v, g = 1, 10, t a = 25 c, unless otherwise noted. (note 6) symbol parameter conditions min typ max units g gain pins 5 and 8 = open 1 pins 5 and 8 = v ref 10 ? g gain error v out = 10v lt1990, g = 1 0.4 0.6 % lt1990a, g = 1 0.07 0.28 % g = 10 0.2 0.8 % gnl gain nonlinearity v out = 10v g = 1 0.0008 0.002 % g = 10 0.005 0.02 % v cm input voltage range guaranteed by cmrr 250 250 v cmrr common mode rejection ratio, rti v cm = 250v to 250v lt1990 60 68 db lt1990a 70 75 db v os offset voltage, rti g = 1, 10 0.9 5.2 mv e n input noise voltage, rti f o = 0.1hz to 10hz 22 v p-p noise voltage density, rti f o = 1khz 1 v/ hz r in input resistance differential 2 m ? common mode 0.5 m ? psrr power supply rejection ratio, rti v s = 1.35v to 18v 82 100 db minimum supply voltage guaranteed by psrr 1.2 1.35 v i s supply current 140 180 a v out output voltage swing 14.5 14.79 v lt1990h symbol parameter conditions min typ max units v os input offset voltage, rti v s = 3v, 0v g = 1, 10 5.2 mv v s = 5v, 0v g = 1, 10 5.2 mv v os /t input offset voltage drift, rti (note 10) 522 v/ c v osh input offset voltage hysteresis, rti (note 11) 250 v psrr power supply rejection ratio, rti v s = 2.7v to 12.7v v cm = v ref = 1.25v 75 db minimum supply voltage guaranteed by psrr 2.7 v i s supply current (note 8) 200 a v ol output voltage swing low ?n = v + , +in = half supply (note 8) 80 mv v oh output voltage swing high ?n = 0v, +in = half supply v s = 3v, 0v, below v + 230 mv v s = 5v, 0v, below v + 275 mv i sc output short-circuit current short to gnd (note 9) 1ma short to v + (note 9) 5ma the denotes the specifications which apply over the temperature range of ?0 c t a 125 c. v s = 3v, 0v; v s = 5v, 0v; r l = 10k, v cm = v ref = half supply, g = 1, 10, unless otherwise noted. (notes 4, 6) 3v/5v electrical characteristics
lt1990 7 1990fb lt1990c/lt1990i symbol parameter conditions min typ max units ? g gain error v out = 10v lt1990, g = 1 0.65 % lt1990a, g = 1 0.33 % g = 10 0.9 % gnl gain nonlinearity v out = 10v g = 1 0.0025 % g = 10 0.025 % g/t gain vs temperature g = 1 (note 10) 2 10 ppm/ c g = 10 (note 10) 7 20 ppm/ c v cm input voltage range guaranteed by cmrr ?50 250 v cmrr common mode rejection ratio, rti v cm = 250v to 250v lt1990 59 db lt1990a 68 db v os input offset voltage, rti g = 1, 10 6.2 mv v os /t input offset voltage drift, rti (note 10) 522 v/ c v osh input offset voltage hysteresis, rti (note 11) 250 v psrr power supply rejection ratio, rti v s = 1.35v to 18v 80 db minimum supply voltage guaranteed by psrr 1.35 v i s supply current 230 a v out output voltage swing 14.4 v i sc output short-circuit current short to v 5ma short to v + 13 ma sr slew rate g = 1, v out = 10v 0.25 v/ s 15v electrical characteristics the denotes the specifications which apply over the temperature range of 0 c t a 70 c. v s = 15v, r l = 10k, v cm = v ref = 0v, g = 1, 10, unless otherwise noted. (notes 4, 6) symbol parameter conditions min typ max units i sc output short-circuit current short to v 69 ma short to v + 15 22 ma bw bandwidth g = 1 105 khz g = 10 7 khz sr slew rate g = 1, v out = 10v 0.3 0.55 v/ s settling time to 0.01% 10v step, g = 1 60 s av ref reference gain to output g = 1 1 0.0007 g = 10 1 0.007 v s = 15v, r l = 10k, v cm = v ref = 0v, g = 1, 10, t a = 25 c, unless otherwise noted. (note 6)
lt1990 8 1990fb lt1990c/lt1990i symbol parameter conditions min typ max units ? g gain error v out = 10v lt1990, g = 1 0.67 % lt1990a, g = 1 0.35 % g = 10 0.95 % gnl gain nonlinearity v out = 10v g = 1 0.003 % g = 10 0.03 % g/t gain vs temperature g = 1 (note 10) 2 10 ppm/ c g = 10 (note 10) 7 20 ppm/ c v cm input voltage range guaranteed by cmrr 250 250 v cmrr common mode rejection ratio, rti v cm = 250v to 250v lt1990 58 db lt1990a 67 db v os input offset voltage, rti g = 1, 10 6.7 mv v os /t input offset voltage drift, rti (note 10) 522 v/ c v osh input offset voltage hysteresis, rti (note 11) 250 v psrr power supply rejection ratio, rti v s = 1.35v to 18v 78 db minimum supply voltage guaranteed by psrr 1.35 v i s supply current 280 a v out output voltage swing 14.3 v i sc output short-circuit current short to v 3ma short to v + 10 ma sr slew rate g = 1, v out = 10v 0.2 v/ s 15v electrical characteristics the denotes the specifications which apply over the temperature range of 40 c t a 85 c. v s = 15v, r l = 10k, v cm = v ref = 0v, g = 1, 10, unless otherwise noted. (notes 4, 6) lt1990h symbol parameter conditions min typ max units ? g gain error v out = 10v lt1990, g = 1 0.69 % lt1990a, g = 1 0.37 % g = 10 0.97 % gnl gain nonlinearity v out = 10v g = 1 0.0035 % g = 10 0.035 % g/t gain vs temperature g = 1 (note 10) 2 10 ppm/ c g = 10 (note 10) 7 20 ppm/ c v cm input voltage range guaranteed by cmrr 250 250 v cmrr common mode rejection ratio, rti v cm = 250v to 250v lt1990 57 db lt1990a 66 db v os input offset voltage, rti g = 1, 10 7.4 mv v os /t input offset voltage drift, rti (note 10) 522 v/ c 15v electrical characteristics the denotes the specifications which apply over the temperature range of 40 c t a 125 c. v s = 15v, r l = 10k, v cm = v ref = 0v, g = 1, 10, unless otherwise noted. (notes 4, 6)
lt1990 9 1990fb lt1990h symbol parameter conditions min typ max units v osh input offset voltage hysteresis, rti (note 11) 250 v psrr power supply rejection ratio, rti v s = 1.35v to 18v 77 db minimum supply voltage guaranteed by psrr 1.35 v i s supply current 330 a v out output voltage swing 14.2 v i sc output short-circuit current short to v 1.5 ma short to v + 7ma sr slew rate g = 1, v out = 10v 0.1 v/ s 15v electrical characteristics the denotes the specifications which apply over the temperature range of 40 c t a 125 c. v s = 15v, r l = 10k, v cm = v ref = 0v, g = 1, 10, unless otherwise noted. (notes 4, 6) note 1: stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. exposure to any absolute maximum rating condition for extended periods may affect device reliability and lifetime. note 2: esd (electrostatic discharge) sensitive device. extensive use of esd protection devices are used internal to the lt1990, however, high electrostatic discharge can damage or degrade the device. use proper esd handling precautions. note 3: a heat sink may be required to keep the junction temperature below absolute maximum. note 4: the lt1990c/lt1990i are guaranteed functional over the operating temperature range of 40 c to 85 c. the lt1990h is guaranteed functional over the operating temperature range of ?0 c to 125 c. note 5: the lt1990c is guaranteed to meet the specified performance from 0 c to70 c and is designed, characterized and expected to meet specified performance from 40 c to 85 c but is not tested or qa sampled at these temperatures. the lt1990i is guaranteed to meet specified performance from 40 c to 85 c. the lt1990h is guaranteed to meet specified performance from ?0 c to 125 c. note 6: g = 10 limits are guaranteed by correlation to g = 1 tests and gain error tests at g = 10. note 7: limits are guaranteed by correlation to ?v to 80v cmrr tests. note 8: v s = 3v limits are guaranteed by correlation to v s = 5v and v s = 15v tests. note 9: v s = 5v limits are guaranteed by correlation to v s = 3v and v s = 15v tests. note 10: this parameter is not 100% tested. note 11: hysteresis in offset voltage is created by package stress that differs depending on whether the ic was previously at a higher or lower temperature. offset voltage hysteresis is always measured at 25 c, but the ic is cycled to 85 c i-grade (70 c c-grade or 125 c h-grade) or 40 c i/h-grade (0 c c-grade) before successive measurement.
lt1990 10 1990fb supply current vs supply voltage supply current vs temperature output voltage swing vs load current output voltage vs input voltage, g = 1 output short-circuit current vs supply voltage input voltage range vs single supply voltage input voltage range vs split supply voltage typical perfor a ce characteristics uw output voltage vs input voltage, g = 10 output voltage swing vs supply voltage g = 1, v +in = v supply current ( a) 220 200 180 160 140 120 100 80 60 40 1990 g01 supply voltage (v) 040 10 20 30 51525 35 t a = 125 c t a = 85 c t a = 40 c t a = 55 c t a = 25 c v ref = v out = 1.25v v = 0v temperature ( c) ?0 ?5 supply current ( a) 100 75 150 140 130 120 110 100 90 80 70 60 1990 g02 0 25 50 125 v s = 5v, 0v output current (ma) 0.001 0.01 0.1 1 10 100 output voltage swing with respect to supply (v) 1990 g03 supply voltage ( v) differential input voltage ( v) differential input voltage ( v) 0 1.0 0.8 0.6 0.4 0.2 0 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 2 4 6 8 10 12 14 16 1990 g06 1990 g05 1990 g04 0.01 0.1 ? +1 +0.1 +0.01 sourcing (+in = 2.5v) sinking (+in = ?.5v) v s = 2.5v ?n = 0v g = 1 t a = 125 c t a = 125 c t a = ?5 c t a = ?5 c t a = 25 c t a = 25 c supply voltage ( v) 1 maximum input voltage (v) 300 200 100 0 100 200 300 711 1990 g09 35 91315 v ref = 0v t a = 40 c to 85 c 0.01 0.1 +0.1 +0.01 output swing with respect to supply (v) 0.01 0.1 ? +1 +0.1 +0.01 output voltage with respect to supply (v) 0.01 0.1 ? +0.1 +1 +0.01 output voltage with respect to supply (v) output fully saturated g = 10 g = 1 g = 10, v +in = v + /10 g = 10, v +in = v /10 g = 1, v +in = v + g = 10 g = 1 output fully saturated v ?n = 0v v ref = 0v no load t a = 25 c v s = 2.5v g = 1 no load v s = 2.5v g = 10 no load t a = 55 c t a = 55 c t a = 125 c t a = 125 c t a = 25 c t a = 55 c t a = 125 c t a = 25 c t a = 55 c t a = 125 c t a = 25 c t a = 25 c positive supply voltage (v) maximum input voltage (v) 250 200 150 100 50 0 ?0 100 1990 g08 1990 g07 3 5 7 9 11 13 15 v = 0v t a = 40 c to 85 c v ref = 1.25v v ref = 1.25v v ref = 4v v ref = 4v v ref = 2.5v v ref = 2.5v supply voltage ( v) 0 output short-circuit current (ma) 25 20 15 10 5 0 ? ?0 ?5 ?0 ?5 ?0 14 12 4 2 6 10 8 16 source sink t a = 55 c t a = 55 c t a = 125 c t a = 125 c t a = 25 c t a = 25 c v v + v v + v v + v v +
lt1990 11 1990fb typical perfor a ce characteristics uw gain vs frequency 3db bandwidth vs supply voltage, g = 1 3db bandwidth vs supply voltage, g = 10 slew rate vs supply voltage, g = 1 slew rate vs supply voltage, g = 10 slew rate vs temperature g = 1 slew rate vs temperature g = 10 common mode rejection ratio vs frequency frequency (hz) gain (db) 50 40 30 20 10 0 ?0 ?0 ?0 ?0 ?0 100 10k 1k 100k 1m 1990 g12 frequency (khz) 1990 g13 120 115 110 105 100 95 90 85 80 75 70 supply voltage ( v) 0 frequency (khz) 16 1990 g14 4 8 12 14 2 6 10 supply voltage ( v) 016 4 8 12 14 2 6 10 8 7 6 5 4 3 slew rate (v/ s) 1.0 0.8 0.6 0.4 0.2 0 1990 g17 slew rate (v/ s) 0.6 0.5 0.4 0.3 0.2 0.1 0 1990 g18 v s = 5v, 0v t a = 25 c t a = 25 c t a = 125 c t a = ?5 c t a = 25 c t a = 125 c t a = ?5 c g = 1 g = 10 t a = 25 c t a = 25 c temperature ( c) ?0 25 75 ?5 0 50 100 125 temperature ( c) ?0 25 75 ?5 0 50 100 125 v s = 15v r l = 10k v s = 15v r l = 10k ?r +sr ?r +sr frequency (hz) 100 common mode rejection ratio (db) 100 90 80 70 60 50 40 30 20 10 0 1k 10k 200k 100k 1990 g10 v s = 5v, 0v t a = 25 c g = 1 or 10 referred to input +sr ?r supply voltage ( v) 0 slew rate (v/ s) 1.0 0.8 0.6 0.4 0.2 0 610 16 1990 g15 24 8 12 14 t a = 25 c r l = 10k +sr ?r supply voltage ( v) 0 slew rate (v/ s) 0.5 0.4 0.3 0.2 0.1 0 610 16 1990 g16 24 8 12 14 t a = 25 c r l = 10k
lt1990 12 1990fb typical perfor a ce characteristics uw warm-up drift vs time settling time vs output step, g = 1 settling time vs output step, g = 10 voltage noise density vs frequency 0.01 to 1hz noise voltage 0.1 to 10hz noise voltage overshoot vs capacitive load output impedance vs frequency power supply rejection ratio vs frequency output step (v) ?0 settling time ( s) 60 50 40 30 20 6 1990 g22 ? ? 4 ? 0 4 8 2 10 output step (v) ?0 6 ? ? 4 ? 0 4 8 2 10 settling time ( s) 320 300 280 260 240 220 200 180 160 140 1990 g23 time (s) 080 1990 g26 20 10 30 50 70 90 40 60 100 time (s) 0 noise voltage (10 v/div) ref noise voltage (10 v/div) ref 8 1990 g25 2 13579 4 6 10 frequency (hz) 10 100 1000 10000 100 1000 1990 g24 voltage noise density (nv/ hz) 1 10000 capacitive load (pf) 10 overshoot (%) 30 25 20 15 10 5 100 1000 10000 1990 g27 0.01% of step 0.01% of step 0.1% of step 0.1% of step 0.01% of step 0.01% of step 0.1% of step 0.1% of step v s = 15v r l = 10k v s = 15v r l = 10k v out = 50mv gain = 1 r l = 10k v s = 1.5v to 15v t a = 25 c v s = 1.5v to 15v t a = 25 c g = 1 v s = 1.5v to 15v t a = 25 c g = 1 v s = 15v v s = 3v, 0v frequency (hz) 10 output impedance ( ? ) 100 1k 5k 100 10k 100k 1990 g19 1 1k 200k frequency (hz) power supply rejection ratio (db) 70 60 50 40 30 20 10 0 ?0 ?0 ?0 ?0 10 1k 10k 1990 g20 100 100k 200k v s = 5v, 0v t a = 25 c g = 1 g = 10 g = 1 g = 10 time after power-up (s) 0 change in offset voltage ( v) 60 40 20 0 ?0 ?0 ?0 10 20 30 40 1990 g21 50 v s = 15v t a = 25 c referred to input v s = 5v, 0v t a = 25 c
lt1990 13 1990fb large signal transient response small signal transient response small signal transient response typical perfor a ce characteristics uw 5v/div v s = 15v g = 1, ? r l = 10k v ref = gnd 50 s/div gnd 1990 g30 50mv/div 50mv/div v s = 15v g = 1, ? r l = 10k v ref = gnd v s = 3v, 0v g = 1, ? r l = 10k v ref = 1.5v 50 s/div 50 s/div gnd 1.5v 1990 g28 1990 g29 + 6 8 5 7 2 3 4 1 v + ?n v +in ref gain1 out gain2 r5 900k r7 10k r10 10k r1 1m r2 1m r6 100k r9 100k r4 40k r3 40k r8 900k 1990 ss block diagra w ref (pin 1): reference input. sets the output level when the difference between the inputs is zero. ?n (pin 2): inverting input. connects a 1m ? resistor to the op amp? inverting input. designed to permit high voltage operation. +in (pin 3): noninverting input. connects a 1m ? resistor to the op amp? noninverting input. designed to permit high voltage operation. v (pin 4): negative power supply. can be either ground (in single supply applications) or a negative voltage (in split supply applications). gain2 (pin 5): gain = 10 select input. configures the amplifier for a gain of 10 when connected to the gain1 pin and the ref pin. the gain is equal to one when both gain2 and gain1 are open. see applications section for addi- tional functions. out (pin 6): output. v out = g ?(v +in ?v ?n ) + v ref , in the basic configuration. v + (pin 7): positive power supply. can range from 2.7v to 36v above the v voltage. gain1 (pin 8): gain = 10 select input. configures the amplifier for a gain of 10 when connected to the gain2 pin and the ref pin. the gain is equal to one when both gain1 and gain2 are open. see applications section for addi- tional functions. uu u pi fu ctio s
lt1990 14 1990fb v cm+ 27 ?v + ?26 ?v ref ?23 ?v gain v cm 27 ?v ?26 ?v ref + 27 ?v gain for split supplies over about 11v, the full 250v common mode range is normally available (with v ref a small fraction of the supply). with lower supply voltages, an appropriate selection of v ref can tailor the input common mode range to a specific requirement. as an example, the following low supply voltage scenarios are readily imple- mented with the lt1990: supply v ref v cm range +3v 1.25v ?v to 25v (e.g. 12v automotive environment) +5v 1.25v ?v to 80v (e.g. 42v automotive environment) +5v 4.00v ?7v to 8v (e.g. telecom environment; use downward signaling) configuring other gains an intermediate gain g ranging between 1 and 10 may be produced by placing an adjustable resistance between the gain1 and gain2 pins according to the following nominal relationship: r gain (180k/(g ?1)) ?20k while the expression is exact, the value is approximate because the absolute resistance of the internal network could vary on a unit-to-unit basis by as much as 30% from the nominal figures and the external gain resistance is required to accommodate that deviation. once ad- justed, however, the gain stability is excellent by virtue of the ?0ppm/ c typical temperature coefficient offered by the on-chip thin-film resistor process. preserving and enhancing common mode rejection the basic difference amplifier topology of the lt1990 requires that source impedances seen by the input pins +in and ?n, should be matched to within a few tens of ohms to avoid increasing common mode induced errors beyond the basic production limits of the part. known source imbalances beyond that level should be compen- sated for by the addition of series resistance to the lower- impedance source. also the source impedance of a signal connected to the ref pin must be on the order of a few ohms or less to preserve the high accuracy of the lt1990. applicatio s i for atio wu u u primary features the lt1990 is a complete gain-block solution for high input common mode voltage applications, incorporating a low power precision operational amplifier providing rail- to-rail output swing along with on-chip precision thin-film resistors for high accuracy. the block diagram shows the internal architecture of the part. the on-chip resistors form a modified difference amplifier including a reference port for introducing offset or other additive waveforms. with pin-strapping alone either unity gain or gain of 10 is produced with high precision. the resistor network is designed to produce internal common-mode voltage divi- sion of 27 so that a very large input range is available compared to the power supply voltage(s) used by the lt1990 itself. the lt1990 is ideally suited to situations where relatively small signals need to be extracted from high voltage circuits, as is the case in many current monitoring instrumentation applications for example. with the ability to accept a range of input voltages well outside the limits of the local power rails and its greater than 1m ? input impedances, development of precision low power over-the-top and under-the-bottom instrumentation de- signs is greatly simplified with the lt1990 single chip solution over conventional discrete implementations. classic difference amplifier used in the basic difference amplifier topology where the gain g is pin-strap configurable to be unity or ten, the following relationship is realized: v o = g ?(v +in ?v ?n ) + v ref to operate in unity gain, the gain1 and gain2 pins are left disconnected. for g = 10 operation, the gain1 and gain2 pins are simply connected to the ref pin. the input common mode range capability is up to 250v, governed by the following relationships: for g = 1 and g = 10 where gain1 and gain2 are only tied together (not grounded,etc): v cm+ 27 ?v + ?26 ?v ref ?23 v cm 27 ?v ?26 ?v ref + 27 for g = 10 where gain1 and gain2 are tied to a common potential v gain :
lt1990 15 1990fb applicatio s i for atio wu uu while the lt1990 comes from the factory with an excellent cmrr, some precision applications with a large applied common mode voltage may require a method to trim out residual common mode error. this is easily accomplished by adding series resistance to each input, +in and ?n, such that an adjustable resistance difference of 1k ? is provided. this is most easily realized by adding a fixed 1k ? in series with one of the inputs, and a 2k ? trimmer in series with the other as shown in figure 1. the trim range of this configuration is 0.1% for the internal gain resistor matching, so a much more finely resolved correction is available using the lt1990 than is realizable with ordinary discrete solutions. in applications where the input common mode voltage is relatively constant and large (perhaps at or beyond the supply range), this same configuration can be treated as an offset adjustment. + lt1990 1k 2k figure 1. optional cmrr trim dual differential-input arithmetic block the internal resistor network topology of the lt1990 allows the gain1 and gain2 pins to be used as another differential input in addition to the normal +in and ?n port. this can be a very useful function for implementing servo-loop differential error amplifiers, for example. in this mode of operation, the output is governed by the following relationship: v o = 10 ?(v +in ? v ?n + v gain2 ?v gain1 ) + v ref unlike the main inputs, the gain1 and gain2 pins are clamped by substrate diodes and esd structures, thus the operating voltage range of these pins is limited to v ?0.2v to v + 36v. if the gain inputs are brought beyond the operating input range, care must be taken to limit the input currents to less than 10ma to prevent damage to the device. for best results in this mode of operation the common mode voltage of the gain1 and gain2 pins should be equal to the ref pin voltage. also, since the gain setting resistors associ- ated with the gain1 and gain2 inputs are in the 10k ? area, low source impedances are particularly important to preserve the precision of the lt1990. this dual differential input mode of operation is used in the circuit as shown in figure 2. this circuit is a high efficiency h-bridge driver that is pwm modulated to provide a controlled current to an electro- magnet coil. since the common mode voltage of the current sense resistor r s varies with operating current and the coil properties, a differential feedback is required. in this application, it was desirable to allow the control input to utilize the wide common mode range port (+in and ?n) so that constraints on input referencing are elimi- nated. the gain1 and gain2 pins always operate within the supply range and both ports operate with a gain of 10 to develop the loop error. the ltc1923 provides the loop integrator and pwm functions of the servo. figure 2. pwm-based 1a electromagnet current controller plllpf r slew sdsync cntrl eaout fb agnd ss i lim r t c t v ref pdrvb ndrvb v dd pgnd ndrva pdrva ltc1923 v dd + lt1990 ref 10k 10k 330pf 1 f 10 f l1 10 h v dd r s 0.1 c1, c2, c3: taiyo yuden jmk325bj226mm-t (x7r) l1, l2: sumida cdrh6d2b-220nc *mna, mpa: siliconix si9801 **mnb, mpb: siliconix si9801 1990 f02 10nf 10nf 1 f 100k 100k 20k 100k 10k 1 f l2 10 h c1 22 f c2 22 f c3 22 f mpa* v ref mpb** mna* mnb** 100k 82k g2 g1 1 4 8 6 5 7 3 2 v in + v in v dd i coil electro- magnet coil 0.1 i coil = (v in + ?v in )/(10 ?r s ) (i.e. 1a for 1v) v thrm h/c v tec i tec tec + tec v set fault cs + cs information furnished by linear technology corporation is believed to be accurate and reliable. however, no responsibility is assumed for its use. linear technology corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
lt1990 16 1990fb ? linear technology corporation 2004 lt 0406 rev b ?printed in usa related parts typical applicatio u part number description comments lt1787 precision high side current sense amplifier on-chip precision resistor array lt1789 micropower instrumentation amplifier micropower, precision, g = 1 to 1000 ltc1921 dual 48v supply and fuse monitor withstands 200v transients lt1991 high accuracy difference amplifier micropower, precision, pin selectable g = 13 to 14 lt1995 30mhz, 1000v/ s gain selectable amplifier pin selectable g = ? to 8 lt6910 single supply programmable gain amplifier digitally controlled, sot-23, g = 0 to 100 telecom supply current monitor selectable gain amplifier bidirectional controlled current source boosted bidirectional controlled current source + lt6650 gnd in out fb 174k 20k 1nf 1 f v ref = 4v 1 2 3 2 6 5 7 4 1 8 4 5 load r s 48v i l + 5v v out 1990 ai01 ?7v v cm 8v v out = v ref ?(10 ?i l ?r s ) lt1990 ref g1 g2 + 3 2 6 7 4 8 5 1 +v ? lt1990 v out v in + v in 1990 ai02 ref 2n7002 2n7002 gain_sel (hi = 10x, lo = 1x) g1 g2 + 3 2 6 7 4 1 +v ? lt1990 i load i load = v ctl /r sense 5ma example: for r sense =100 ? , output is 1ma per 100mv input v ctl r sense 1990 ai03 ref + 3 2 6 7 4 1 +v ? lt1990 i load i load = v ctl /r sense 100ma example: for r sense =10 ? , output is 1ma per 10mv input v ctl r sense 1990 ai04 10 f 1k 1k ref czt751 czt651 + package descriptio u .016 ?.050 (0.406 ?1.270) .010 ?.020 (0.254 ?0.508) 45 0 ?8 typ .008 ?.010 (0.203 ?0.254) so8 0303 .053 ?.069 (1.346 ?1.752) .014 ?.019 (0.355 ?0.483) typ .004 ?.010 (0.101 ?0.254) .050 (1.270) bsc 1 2 3 4 .150 ?.157 (3.810 ?3.988) note 3 8 7 6 5 .189 ?.197 (4.801 ?5.004) note 3 .228 ?.244 (5.791 ?6.197) .245 min .160 .005 recommended solder pad layout .045 .005 .050 bsc .030 .005 typ inches (millimeters) note: 1. dimensions in 2. drawing not to scale 3. these dimensions do not include mold flash or protrusions. mold flash or protrusions shall not exceed .006" (0.15mm) s8 package 8-lead plastic small outline (narrow .150 inch) (reference ltc dwg # 05-08-1610)

▲Up To Search▲

Price & Availability of LT1990HS8PBF

	To Download LT1990HS8PBF Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .