.SUBCKT LM411 1 2 99 50 28 * | | | | | * | | | | '--- Output * | | | '------- Negative power supply (ground) * | | '----------- Positive power supply * | '--------------- Inverting input * '------------------- Non-inverting input * Use the gSchem symbol opamp-3.sym (provided in the lib/sym directory) *////////////////////////////////////////////////////////////////////// * (C) National Semiconductor, Inc. * Models developed and under copyright by: * National Semiconductor, Inc. *///////////////////////////////////////////////////////////////////// * Legal Notice: This material is intended for free software support. * The file may be copied, and distributed; however, reselling the * material is illegal *///////////////////////////////////////////////////////////////////// * For ordering or technical information on these models, contact: * National Semiconductor's Customer Response Center * 7:00 A.M.--7:00 P.M. U.S. Central Time * (800) 272-9959 * For Applications support, contact the Internet address: * amps-apps@galaxy.nsc.com *///////////////////////////////////////////////////////////////////// * LF411 Low Offset, Low Drift JFET Input Op-Amp Macro-model. * * Features : * Fast settling time (.01%) = 2uS * High bandwidth = 3MHz * High slew rate = 10V/uS * Low offset voltage = 0.5mV * Low supply current = 1.8mA * * Note : Input resistance (Rin) for these JFET op amps is 1TOhm. Rin * is modeled by assuming the option GMIN = 1TOhm. If a different * (non-default) GMIN value is needed, users may recalculate as * follows : * Rin = (R1 || GMIN+R2 || GMIN) where R1=R2, * to maintain a consistent Rin model. * ****************INPUT STAGE************** * IOS 2 1 25.0P * Input offset current CI1 1 0 3P CI2 2 0 3P R1 1 3 1E12 R2 3 2 1E12 I1 99 4 1.0M J1 5 2 4 JX J2 6 7 4 JX R3 5 50 650 R4 6 50 650 *Fp2=28 MHZ C4 5 6 4.372P * ***********COMMON MODE EFFECT*********** * I2 99 50 800UA * Quiescent supply current EOS 7 1 POLY(1) 16 49 .8E-3 1 * Input offset voltage. R8 99 49 80K R9 49 50 80K * *********OUTPUT VOLTAGE LIMITING******** V2 99 8 2.13 D1 9 8 DX D2 10 9 DX V3 10 50 2.13 * **************SECOND STAGE************** * EH 99 98 99 49 1 G1 98 9 5 6 20E-3 R5 98 9 10MEG VA3 9 11 0 * Fp1 = 18HZ C3 98 11 857.516P * ***************POLE STAGE*************** * * Fp = 30MHz G3 98 15 9 49 1E-6 R12 98 15 1MEG C5 98 15 5.305E-15 * *********COMMON-MODE ZERO STAGE********* * G4 98 16 3 49 1E-8 L2 98 17 144.7M R13 17 16 1K * **************OUTPUT STAGE************** * F6 99 50 VA7 1 F5 99 23 VA8 1 D5 21 23 DX VA7 99 21 0 D6 23 99 DX E1 99 26 99 15 1 VA8 26 27 0 R16 27 28 50 V5 28 25 0.646V D4 25 15 DX V4 24 28 0.646V D3 15 24 DX * ***************MODELS USED************** * .MODEL DX D(IS=1E-15) .MODEL JX PJF(BETA=1.183E-3 VTO=-.65 IS=50E-12) * .ENDS