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Simulators >> Circuit Simulators >> Strange Issue while simulating an Oscillator - Important
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Message started by gajular on May 25^th, 2016, 10:27pm

Title: Strange Issue while simulating an Oscillator - Important
Post by gajular on May 25^th, 2016, 10:27pm

I am working on the design of an oscillator. I have attached a snapshot of the schematic to this message. In the schematic I have used an isource instance I40 which remains open. The oscillator build up is varying depending on the frequency that I give in I40 instance. In this case the oscillator is building up faster with increase in frequency in I40 instance. I am not able to contemplate why the oscillation build up is dependent on the frequency in I40 which is no where connected to the circuit.

I am running transient analysis. Please find the schematic and netlist attached to this message.

Title: Re: Strange Issue while simulating an Oscillator
Post by gajular on May 25^th, 2016, 10:29pm

Please find the netlist attached to this message

Title: Re: Strange Issue while simulating an Oscillator - Important
Post by Ken Kundert on May 28^th, 2016, 10:58am

By having an active current source driving an open circuit you are causing those nodes to shoot up to extremely high voltages. This will destroy the error control of the simulator unless you take certain steps to counter it.

Don't do that.

Also, don't ask simulation questions in the design boards.

-Ken