CD4000 Vdd

[ronv]

I have the CD4000 library for LTSpice kindly provided by Eric G. I can change the VDD say 5 volts or 9 volts in the attribute editor and all the thresholds and stuff change. Cool.
But if I want to depend on the thresholds during power up or down the Vdd needs to track the circuit supply voltage. Is there an easy way to do this?

 

[eTech]

I have the CD4000 library for LTSpice kindly provided by Eric G. I can change the VDD say 5 volts or 9 volts in the attribute editor and all the thresholds and stuff change. Cool.
But if I want to depend on the thresholds during power up or down the Vdd needs to track the circuit supply voltage. Is there an easy way to do this?

Hi

Place a wire label named "VDD" on the voltage source. That basically connects the cd4000 component internal "VDD" nets to that source.

eT

 

[ronv]

Thanks! I'll try it.

 

[eTech]

Thanks! I'll try it.

One thing I forgot to mention...

For my suggestion to work, you need to use the CD4000_v.lib library file. This library has been modified to provide access to the internal device power pins.

eT

 

[ronv]

Ahh, That would explain it.
I can't seem to get the symbol files from LTSpice could you share yours?

 

[eTech]

Sure...

 

[ronv]

Thanks! I got it going.