555 simulation on ORCAD9

[Tetra]

simulation du 555

I tried to simulat 555 circuits on Orcad9.0. The Anl_Misc contains three Model 555B, 555C, 555alt. 555B only passed without errors but simulation output do not work at all. anyone can help?

 

[flatulent]

examine subcircuit

Examine the subcircuit models with a text editor. You will see commented lines that look like they should be uncommented and the proper component values filled in.

There are other tricks like this in OrCAD. The 74 family of monostable models require you to edit them to specify the pulse widths which are not a function of the R and C put on the outside terminals.

To keep from modifying the library files, copy and paste the subcircuit description to your .net list and modify it there.