I have a big problem in simulating a inverter in Hspice !

[shaq]

Dear all,
When I use "hspice" to simulate my inverter,it can pass!
Then I use "awaves" to see my input/output waves, the output wave is zero!
What's wrong with my netlist?

This is my netlist.

********************************************************************
* auCdl Netlist:
*
* Library Name: Inverter
* Top Cell Name: inv
* View Name: schematic
* Netlisted on: Sep 15 20:30:50 2005
********************************************************************

*.EQUATION
*.SCALE METER
*.MEGA
.PARAM

.GLOBAL gnd!
+ vdd!

*.PIN gnd!
*+ vdd!

*****************************************************************
*Library Name: Inverter
* Cell Name: inv
* View Name: schematic
*****************************************************************

.SUBCKT inv in out
*.PININFO in:I out:O
MM1 out in gnd gnd nch W=700n L=350n M=1
MM0 out in vdd vdd pch W=700n L=350n M=1
.ENDS

VVDD VDD gnd 5
VIN IN GND PULSE 0 5 .5n .1n .1n .5n 2n
CLOAD OUT gnd 100f

.OPTIONS POST
.TRAN/op 200p 20n
.PRINT TRAN V(in) V(out)
.END

 

[Hughes]

You didn't apply the power supply to the inverter.
Nodes vdd! and gnd! were declared as global, but the inverter's power-rails are vdd and gnd.
Change vdd! to vdd in the .global statement.

 

[shaq]

Re: I have a big problem in simulating a inverter in Hspice

Hello Hughes,

I've changed vdd! to vdd and gnd! to gnd,but the output is still zero.

Can anyone help me to solve this problem?

 

[Hughes]

Oh, your netlist is strange enough. You didn't instantiate the inverter!
Add a line to the netlist:
X1 in out inv

 

[shaq]

Re: I have a big problem in simulating a inverter in Hspice

Thank you,Hughes!

I solve it already!

This is my new netlist.
It works fine!
*******************************************
*.EQUATION
*.SCALE METER
*.MEGA
.PARAM

.GLOBAL vdd! gnd!

*.PIN gnd!
*+ vdd!
vdd vdd! 0 5

.SUBCKT inv in out
*.PININFO in:I out:O
MM1 out in gnd! gnd! nch W=700n L=350n M=1
MM0 out in vdd! vdd! pch W=700n L=350n M=1
.ENDS inv

X1 in out inv
vin in 0 0 PULSE 0 5 .5n .1n .1n .5n 2n
CL out 0 1f

.MODEL PCH PMOS LEVEL=1
.MODEL NCH NMOS LEVEL=1
.OPTIONS POST
.TRAN 200p 20n
.PRINT TRAN v(in) v(out)
.END
*******************************************

 

[wjxcom]

HI,shaq, what's difference between the old netlist and the new netlist? I think thay are the same!!

 

[Hughes]

Re: I have a big problem in simulating a inverter in Hspice

HI,shaq, what's difference between the old netlist and the new netlist? I think thay are the same!!

The differences are mentioned above:
One is the power nets. The first netlist decalre global nets vdd! and gnd!, but the inverter's power nets are vdd and gnd. The second netlist changes them to vdd! and gnd!.
Another difference is that the second netlist has a line to instantiate the inverter:
X1 in out inv