Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Pulse voltage problem in Hspice

Status
Not open for further replies.

discover93

Newbie level 5
Joined
Mar 2, 2018
Messages
8
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
45
I am new to the whole subject so please bear with me. I write a simple problem for nand gate in Hspice and as input I used two pulse voltage. However the wave I get is not a pulse. Here is my code and waves:

Code:
# NAND2 

.include ./22nm_lp.pm.txt

M1 c a 1 1 pmos l=22n w=44n *Ap
M2 c b 1 1 pmos l=22n w=44n *Bp 

M3 c a 2 2 nmos l=22n w=22n *An
M4 2 b 0 0 nmos l=22n w=22n *Bn

vdd 1 0 dc 0.95V
vb b 0 pulse 0.95 0 0 5n 5p 95p 200p 
va a 0 pulse 0.95 0 0 5p 5p 95p 200p 

.option post accurate nomod
.MEASURE TRAN delay TRIG V(b) VAL=0.475  RISE=1
+                   TARG V(c) VAL=0.475  FALL=1
.tran 200p 1000p

.end

co.png

Can anyone please explain what's going on?
 

You get out what you put in. Why did you set vb rise time to 5 ns?

Apart from this point, the output voltage suggests that the transistor parameters aren't suited for the 0.95V operation.

If the circuit is somehow related to IC design, we would expect all substrates tied to VDD and GND, not floating like M3.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top