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Simulators >> Circuit Simulators >> Measure capacitance of a node in ring oscillator
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Message started by baab on Dec 10^th, 2015, 11:53pm

Title: Measure capacitance of a node in ring oscillator
Post by baab on Dec 10^th, 2015, 11:53pm

I would like to measure the capacitance between a node to ground in my ring oscillator.
I am running transient analysis. As you see the oscillator have no input and output.
Is there a way to do that in Cadence?

Title: Re: Measure capacitance of a node in ring oscillator
Post by raja.cedt on Dec 14^th, 2015, 11:42pm

Add a dc current source with 0mA dc and 1A ac value. Run transient and note down the time period. Do a ac times sim over the time period. Now you can find ac voltage on that node over the period. You have voltage and current hence find the cap.
Ps: cap corresponding to a node in ring oscillator varies over the period, for the oscillation frequency calculation, I would suggest use mid rail cap.

Best Regards,
Raj.