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gEDA-user: Opamp Model vs Open Loop Gain
I was seeing unexpected results from simulating a circuit and decided
to replicate the datasheet.
For the LF353/NS, openloop gain is 115db to 20Hz with a linear drop to
zero at 5MHz, more or less. Vs=+-15, Rl=2K.
I assumed this to be with the non-inverting input grounded, AC to the
inverting input, and 2K to ground from the output.
I see 15db to 100KHz with a drop to zero at 5MHz. I expected the
model to be similar to the datasheet.
The circuit is
* LF353 MODEL TEST vs DATA SHEET
Vin 2 0 DC 0 AC .001 0
Vp 4 0 +15
Vn 5 0 -15
R3 6 0 2K
X1 0 2 4 5 6 LF353/NS
.include ../opamp/lf353_sp3.mod
Spice> run
Spice> ac dec 100 1 10Meg
Spice> plot db(v(6)/v(2))
What am I doing wrong?
tomdean