SOLVED! - OrCAD Pspice Simulation help - 4bit counter

Thread Starter

odm4286

Joined Sep 20, 2009
265
Hello, can someone take a look at my simulation settings and let me know what I am doing wrong? For some reason, my counter outputs never change state. Played around with this for about an hour or so, I know there is some setting I am missing somewhere. Any help is appreciated.

1639099715759.png


1639099739777.png
 

eetech00

Joined Jun 8, 2013
3,110
Hello, can someone take a look at my simulation settings and let me know what I am doing wrong? For some reason, my counter outputs never change state. Played around with this for about an hour or so, I know there is some setting I am missing somewhere. Any help is appreciated.
The 74393 clock input is active low.
Try pulling the clock input high to 5v (instead of low) thru the resistor.
The PB should produce a signal from "open" to low(GND) to clock the 393.
(Use a switch (or PB) component for the PB)
 
Last edited:

Thread Starter

odm4286

Joined Sep 20, 2009
265
Perhaps you have a bad model.
Did it come with OrCad Pspice?
Yep, came with the software. From what I've read, the red lines indicate the line is at an indeterminate logic level. I've tried two different counters and have the same issue by the way.

Anything special I need to do in my simulation profile?
 
Top