How to simulate 18V CMOS circuit in pspice

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I have a circuit whree I have to interface 5V TTL 7400 ic with 4500 series 4538b IC and achieve 18V signals.
I need to do the orcad pspice simulation of the circuit.
please help
 

A TTL output high is only about +3.5V.
A Cmos IC operating from a supply as high as 18V needs an input high that is at least +13.2V.
Orcad might not know this.

So you need a level translator circuit to boost +3.5V to +13.2V.
 

I want to build a level translator which can be simulated.
When I try to apply 18V (or any value more than 8V) as VDD the IC gives error

" Digital input voltage hazard at time 0s"
Device: X$VDD_AtoD1.O0
Voltage V(X$VDD AtoD1.NORM.0) = 3.7500 is beyond ranges defined in model DO4000B


I have used this circuit.


please explain
How can I use 18V toggling with the CMOS gates
 

Your simulation program probably has the specs for a Cmos logic IC only with a supply up to 8V.
The spec's are completely different above 8V.
What does your SIM program do when the supply is only 3V?
 

Looks like your model is a behavioral type with too much range
checking etc.

Here is somebody's page with a more analog-y CD4538 model
:
http://www.gunthard-kraus.de/Spice_Model_CD/Vendor List/Spice-Models-collection/1_shot.lib

(all the way down).

Now to interface cleanly, you might need to interpose something
like a switching NPN with collector pulled up to +18V, and drive
its base with your 74xx gate through a limiting resistor. It'll be
slow, it'll eat power, but it's all just coursework, right?
 

the pspice model that I have used for the circuit is same one as you suggested .
with follwing difference


can you please tell me the how can I add these pins to my IC.
CX and RXCX pins.

- - - Updated - - -

Update: I have added these pins of RXCX and CX in the design. they do not affect the simulation. I am still getting error as


in the pspice simulation
 

Has anyone ever simulated 4000 series cmos ics successfully in any circuit?
 

I designed and built many 4000 series Cmos logic circuits. None were simulated but every circuit worked perfectly.
 

I am simulating a larger system. The high voltage IGBT driver IC takes input of these CMOS ic outputs. Hence I have to simulate the CMOS Ics.
 

The error was to show the power pins and connect the proper voltages to the power pins solved the problem.
 

Maybe it helps. Everything about it is explained in PSpice User Manual (attached).
 

Attachments

  • SCHEMATIC1_TP's.pdf
    19.1 KB · Views: 106
  • Specifying digital power supplies.pdf
    183.1 KB · Views: 367
  • SCHEMATIC1_Sig's.pdf
    34.5 KB · Views: 94

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