Symbol Names: MESFET
Syntax: Zxxx D G S model [area] [off] [IC=<Vds, Vgs>]
+ [temp=<value>]
A MESFET transistor requires a model card to specify its characteristics. The model card keywords NMF and PMF specify the polarity of the transistor. The MESFET model is derived from the GaAs FET model described in H. Statz et al., GaAs FET Device and Circuit Simulation in SPICE, IEEE Transactions on Electron Devices, V34, Number 2, February, 1987 pp160-169.
Two ohmic resistances, Rd and Rs, are included. Charge storage is modeled by total gate charge as a function of gate-drain and gate-source voltages and is defined by the parameters Cgs, Cgd, and Pb.
|
Name |
Description |
Units |
Default |
|
Vto |
Pinch-off voltage |
V |
-2. |
|
Beta |
Transconductance parameter |
A/V² |
1e-4 |
|
B |
Doping tail extending parameter |
1/V |
0.3 |
|
Alpha |
Saturation voltage parameter |
1/V |
2. |
|
Lamda |
Channel-length modulation |
1/V |
0. |
|
Rd |
Drain ohmic resistance |
W |
0. |
|
Rs |
Source ohmic resistance |
W |
0. |
|
Cgs |
Zero-bias G-S junction capacitance |
F |
0. |
|
Cgd |
Zero-bias G-D junction capacitance |
F |
0. |
|
Pb |
Gate junction potential |
V |
1. |
|
Kf |
Flicker noise coefficient |
- |
0. |
|
Af |
Flicker noise exponent |
- |
1. |
|
Fc |
Forward-bias depletion coefficient |
- |
0.5 |