Author Topic: 4028 chip in LTSpice subcircuit  (Read 5534 times)

0 Members and 1 Guest are viewing this topic.

Offline lamjaTopic starter

  • Contributor
  • Posts: 20
    • Lamja.com
4028 chip in LTSpice subcircuit
« on: August 07, 2010, 04:26:42 am »
Just wanted to share my 4028 simulation in LTSpice.

I made it as an subcircuit by first creating an equivalent circuit.


Then I labeled the nets used by the chip



The voltage sources are actually arbitary behavioral voltage sources to simulate the output of the 4028 chip.
B1 : V=(!(V(In3)) & !(V(In2)) & !(V(In1)) & !(V(In0)))*V(Vdd)                     (logical AND of all inverse In signals times Vdd)
B2 : V=(!(V(In3)) & !(V(In2)) & !(V(In1)) & (V(In0)))*V(Vdd)
B3 : V=(!(V(In3)) & !(V(In2)) & (V(In1)) & !(V(In0)))*V(Vdd)
B4 : V=(!(V(In3)) & !(V(In2)) & (V(In1)) & (V(In0)))*V(Vdd)
...
B10 : V=((V(In3)) & !(V(In2)) & !(V(In1)) & (V(In0)))*V(Vdd)                      (logical AND of all In signals times Vdd)


Then save this file as 4028.asc

Then you have to create a symbole


Create the pins


Add the same Labels you used in the .asc-file. Netlist Order should be the pin number on the chip. If you use for example number 16, all pins from 1-15 must also be defined.


Save the files as 4028.asy in the same folder as the .asc-file.
I made an extra folder in the "sym"-folder of LTSpice to have my chip located in.


Then I made a test circuit with two cascading 4028's


Thats it. Then there is only about 200 chips to go...

I attach the files to save you some work if you're interrested in checking it out.
 

Offline gbowne1

  • Contributor
  • Posts: 15
Re: 4028 chip in LTSpice subcircuit
« Reply #1 on: September 06, 2010, 08:48:02 am »
I'm still learning LTSpice IV v4.09.  I also just got Cadsoft Eagle 5 off the site.

But I have some old circuits I'm trying to debug and update them because about half the components used are old and no longer available.

Took me a while to move from the old hand drawn schematics to the model space onto the board level.

One of them involves a complex RF board that I did in the 1980s.  I have to move the board design from a muliti-board layout to a backplane style and a large main board, PLL, PSU and other things. Its quite a mess.  I could use some help.

Thanks for the visiualization of the CD4028, etc model.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf