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Help with HSPICE subcircuit

P

Patrick

Jan 1, 1970
0
hello,
i'm new to hspice and i'm trying to make a 2-input NAND gate
subcircuit so that i can go on to simulate more complex circuits using
this NAND gate. i wrote a short netlist just to test my NAND gate
subcircuit (shown below). i basically tied one input to +5V and put a
clock signal into the other input.
whenever i run the simulation, i get a "hspice job aborted" message
because of some error. i have no idea what i'm doing wrong. i included
the two model files (nmos.spi and pmos.spi) in my working directory
and i've successfully used these models before for other simpler
simulations (without any subcircuits). i would greatly appreciate any
help i can get. thanks in advance,
patrick antoun



NAND Gate Trial
..OPTIONS LIST NODE POST
..TRAN 200P 42N
..PRINT TRAN V(OUT)

*OUTPUT---------------|
*INPUT B------------| |
*INPUT A----------| | |
*GND------------| | | |
*VDD----------| | | | |
..SUBCKT 2NAND 1 2 3 4 6
M1 6 3 1 1 PCH L=1U W=20U
M2 6 4 1 1 PCH L=1U W=20U
M3 6 3 5 5 NCH L=1U W=20U
M4 5 4 2 2 NCH L=1U W=20U
..MODEL PCH PMOS LEVEL=1
..MODEL NCH NMOS LEVEL=1
..ENDS 2NAND

VDD VDD 0 5
VA A 0 5
VCLK B 0 0 PULSE 0 5 1F .1N .1N 10N 21N
X1 VDD 0 A B OUT 2NAND

..MODEL PCH PMOS LEVEL=1
..MODEL NCH NMOS LEVEL=1

..END
 
J

Jim Thompson

Jan 1, 1970
0
hello,
i'm new to hspice and i'm trying to make a 2-input NAND gate
subcircuit so that i can go on to simulate more complex circuits using
this NAND gate. i wrote a short netlist just to test my NAND gate
subcircuit (shown below). i basically tied one input to +5V and put a
clock signal into the other input.
whenever i run the simulation, i get a "hspice job aborted" message
because of some error. i have no idea what i'm doing wrong. i included
the two model files (nmos.spi and pmos.spi) in my working directory
and i've successfully used these models before for other simpler
simulations (without any subcircuits). i would greatly appreciate any
help i can get. thanks in advance,
patrick antoun



NAND Gate Trial
.OPTIONS LIST NODE POST
.TRAN 200P 42N
.PRINT TRAN V(OUT)

*OUTPUT---------------|
*INPUT B------------| |
*INPUT A----------| | |
*GND------------| | | |
*VDD----------| | | | |
.SUBCKT 2NAND 1 2 3 4 6
M1 6 3 1 1 PCH L=1U W=20U
M2 6 4 1 1 PCH L=1U W=20U
M3 6 3 5 5 NCH L=1U W=20U
M4 5 4 2 2 NCH L=1U W=20U
.MODEL PCH PMOS LEVEL=1
.MODEL NCH NMOS LEVEL=1
.ENDS 2NAND

VDD VDD 0 5
VA A 0 5
VCLK B 0 0 PULSE 0 5 1F .1N .1N 10N 21N
X1 VDD 0 A B OUT 2NAND

.MODEL PCH PMOS LEVEL=1
.MODEL NCH NMOS LEVEL=1

.END

It's probably throwing up on the DELAY term in the Pulse description,
1F = 1 femto-second, 1e-15

Make it perhaps 1N, or 0 (zero)

If you have a model "card" you don't have to describe the model again
from within the subcircuit.

In the "real world" CMOS is (usually) P-type substrate. This means
the bodies of the NMOS must connect to ground. (There are dual-well
processes, but not usually found in a student environment :)

...Jim Thompson
 
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