How to calculate impedances at nodes ina circuit in HSPICE

[engrvip]

Can any one tell how can i calculate impedance at particular node in my circuit in HPSICE????

 

[hr_rezaee]

Hi
connect a ac volatge source with amplitude of 1v (ac) at your paticular node and then 1/I(ac source) is your Impedance.
don't forget use of .ac analysis.
regards

 

[engrvip]

1/I(ac source)......is this current thru the ac source ...but how will this represent impedance ...plz ealborate????

 

[analog_guru]

Re: How to calculate impedances at nodes ina circuit in HSPI

This is very basic circuit question!.. This is called Thevenin equivalent!

 

[hr_rezaee]

Re: How to calculate impedances at nodes ina circuit in HSPI

This is very basic circuit question!.. This is called Thevenin equivalent!

Hi
Yes it is true.
your ac amplitude is 1v so output impedance is V/I=1/I.
It is similar to theoriy (technique that we use in manual computation).
regards

 

[devop]

can .TF analysis get the impedance?

 

[hr_rezaee]

Re: How to calculate impedances at nodes ina circuit in HSPI

can .TF analysis get the impedance?

Hi
.TF gives Transfer function of a node.
you can find gain, zeros and poles from it.
regards

 

[engrvip]

transfer impedance gives impedance at output node ( whatever u take it ) ...so is that sufficient to calculate impedance at that node...