Internal Impedance of sources

[Ramakrishna_444]

What’s the exact Internal impedance values of vdc and idc of analogLib in Cadence Virtuoso Design Environment...?


Please do enlighten me in this concern......

Thanks in advance.......

 

[Serfacy]

In SPICE-like software ideal vdc has 0 and ideal idc infinite impedance.

 

[Ramakrishna_444]

Serfacy,

Thanks a lot for your reply....

But how would they define INFINITE in scripting......?

 

[Serfacy]

The real voltage source can be represented as serial connection of ideal vdc and imperance Z (this is zero for ideal case). Current source is usually represented as parallel connection of ideal current source and admittance. Admittance Y = 1/Z. In ideal case Y=0, which gives Z = infinite. Thus you can use admittance instead of impedance.

 

[Ramakrishna_444]

Serfacy,

Thanks a lot for your reply....

BUT

In scripting the width of the variable holding data is FINITE. INFINITE means the largest possible thing.

For Example the width of the variable holding data is 4. The largest possible number is 9999 (in Decimal Number System)....?

 

[Serfacy]

Yes you are right and that is why I suggested you to use admittance instead of impedance. Its value is 0.

 

[Ramakrishna_444]

Serfacy,

By the same token,

The Internal impedance of Current source in Bounded and Convergent System should be THE LARGE possible value. So idc of analogLib in Cadence Virtuoso Design Environment would be....?

 

[FvM]

I presume, idc is not the impedance parameter, just current. It surely has to be finite.

Secondly. Circuit simulators have general parameters limiting the impedance of any node to a large final value, respectively the admittance to small value > 0. They also affect the behavior of sources. Without specifying an impedance explicitly, it's still limited.

 

[Ramakrishna_444]

Thanks a lot for your reply.....

What’s the exact Internal impedance values of vdc and idc of analogLib in Cadence Virtuoso Design Environment...?