"How to simulate output resistance in Hspice"

[cqmyg5]

simulate output resitance

Dear All,

I'm confused with this problem for long time. could anyone give me a instruction?

Thanks!

 

[mazelk]

hspice resistance

Hi....

You can use .tf command in order to get output resistance, input resistance, voltage gain, etc...

 

[bastos4321]

hspcie resistance

You can use the definition of output resistance. Just connect an AC voltage source to the output and measure the current. The output resistance is given by ohms law V/I.

I use this approach to find output resistance of complex blocks.

bastos

 

[cqmyg5]

hspice output resistance

to bastos4321:

Does this AC source have DC voltage? as:

A: vx vout gnd ac=1mv
B: vx vout gnd dc=1.5v ac=1mv

use A or B?

Thanks!

 

[stanlangley]

Should we connect the input to ground before conduct the simulation to calculate the output resistance?

Stan

 

[andy2049]

I think you need to connect the input to ground accroding to the definition.