Question

How would I simulate an Ideal Differential op amp in a NETLIST in LTSPICE IV?

What is the NETLIST line of code?

Answer 1

Differential amplifier configuration::

We simulate the ideal op amp as a voltage-controlled voltage source (VCVS) with extremely high gain. Inabove figure “e” is the opamp with differential input applied to the nodes 2(non-inverting) and 4(inverting) and output measured at the nodes 5 and 0(ground). The voltage gain of the VCVS i.e. the input impedence of the opamp is set at 999k.

Netlist code:

vi1 1 0 dc V1 ;replace V1 with value of non-inverting input voltage

vi2 3 0 dc V2 ;replace V1 with value of inverting input voltage

e 5 0 2 4 999k ;simulation of opamp as VCVS

r1 1 2 R1 ;replace R1, R2, R3, Rf with actual values of corresponding resistances

r2 2 0 R2

r3 4 3 R3

rf 5 4 Rf

.end