opamp in the cyclic adc

[A.jafari]

Hi.
I designed an Opamp with Hspice software but when I want to use it in the pipeline ADC in MDAC circuit it doesn't work.
Does anybody can help me?

 

[BradtheRad]

Things that might affect operation in one or the other simulator.

* Does the op amp need to have a visible power supply hooked up? Or is the power supply understood to be present?

* Are you required to specify a particular range of output? From 0V to positive supply rail? Or negative rail to positive rail?

* Are you required to specify an output impedance?

 

[A.jafari]

I'm sorry I don't understand you. could you say clearly?
Thanks.
Best wishes
A.Jafari

 

[BradtheRad]

Example diagrams to show how one simulator creates an op amp and its specs.



A different simulator might have a different format. Or a different naming system.

These could be reasons why your op amp works in one simulator but not in the other.

 

[A.jafari]

Hi.Thank you for your reply.
my problem doesn't relate to simulation software.
I said when i implemented my Opamp in the MDAC circuits my ADC doesn't work?
My question is that what is critical factor to design an Opamp and use it in the pipeline ADC or cyclic ADC?
My ADC type is cyclic with 20 MS/s in sampling rate and 12 bit in the resolution.

 

[naveensai12]

Can you please post the MDAC structure you are using ???

 

[A.jafari]

This is my Mdac Structure.