Hi,
I want to know how to vary a parameter inside a model and get the results in one run (one simulation). I've given a simple circuit below that I would also want to do .TRAN and .AC analysis on. (Like run an AC response for three transistor values of Bf.) I've managed to do .TEMP parameterization, but I can't figure out how to do something like Bf.
For the purpose of example, what syntax would I add to parameterize the Beta_forward (Bf) to values of 50, 125, and 300? (The model is the one that comes with LTSPICE, BTW.)
I have been trying to learn on the latest version LTSPICE, if that matters.
Thanks, Pete
Here is an example circuit:
---------------------------
2n3904_00
- Vcc
- .-----.
- | |
- ---V1 |
- - 5V .-.
- | | |R1
- === | |2k7
- GND '-'
- |
- .-----o
- | |
- .-. |Vc
- | |R3 |
- | |13k |
- '-' |
- |Vb |/ 2n3904
- o---| Q1
- | |>
- .-. |
- | |R2 |
- | |6k8 |
- '-' |
- | |
- '-----o
- |
- ===
- GND
*
*
*(created by AACircuit v1.28.6 beta 04/19/05
Q1 Vc Vb 0 0 2N3904 R1 Vcc Vc 2.7k R2 Vb 0 6.8k R3 Vc Vb 13k V1 Vcc 0 5 .model 2N3904 NPN (
+IS=1E-14
+VAF=100
+Bf=300
+IKF=0.4
+XTB=1.5
+BR=4
+CJC=4E-12
+CJE=8E-12
+RB=20
+RC=0.1
+RE=0.1
+TR=250E-9
+TF=350E-12
+ITF=1
+VTF=2
+XTF=3
+Vceo=40
+Icrating=200m
+mfg=Philips
+) .op .end