Originally Posted by Hero999

I've RTFM for the TLC model and it seems like the value of Vdd is only used to calculate the output MOSFET on resistance which varies with the supply voltage.

It looks I'm doing it the right way, run the simulation, find out the supply voltage, run it again, paste the calculated supply voltage into the model's properties box and run it again and paste the newly calculated supply voltage into the properties box. The second guess is always pretty accurate.

The on resistance only matters when R1 or R2 are set to low values, when they're both 50k, it doesn't make any difference.

hi,
I have run your asy file of the hero Mk1 7555 OK, with the original test asc file.

Lets know if you make any other changes.

What's that you say you've tested the better looking symbol I posted and it worked?

I couldn't get it to work, there must have been somthing I was doing wrong, please enlighten me.

EDIT:
Please post the .asc file.

Originally Posted by Hero999

What's that you say you've tested the better looking symbol I posted and it worked?

I couldn't get it to work, there must have been somthing I was doing wrong, please enlighten me.

EDIT:
Please post the .asc file.

This is how I tried it, you must include the sub circuit.

Yes, it works.

I hope you agree, that the schematic is much easier to follow now.