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IvoryDesigner

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Posts: 10

Simulate slew rate of a fully differentiel amplifier
Mar 11^th, 2010, 1:20pm

Hi,
I'm simulating performances of a fully differential OpAmp, and I would like to know How to simulate the Slew rate. I know how to do it with a single ended OpAmp: Set the OpAmp into follower configuration and enter a pulse at the input and look at the output.

Is it the same with a fully differential OpAmp??

Thank you for your help!

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sheldon

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Posts: 751

Re: Simulate slew rate of a fully differentiel amplifier
Reply #1 - Mar 12^th, 2010, 10:14pm

Ivory,

� Maybe I am missing something, but why don't you just measure
slew rate of the amplifier in the application test bench? That is, input
a pulse into your circuit and measure the slew rate. The slew rate is
dependent on context, that is, the circuit architecture.

� � � � � � � � � � � � � � � � � � � � � � � � � � � � � �Best Regards,

� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � Sheldon

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IvoryDesigner Junior Member Offline Posts: 10	Re: Simulate slew rate of a fully differentiel amplifier Reply #2 - Mar 13^th, 2010, 7:38pm Hi Sheldon, Thanks for your answer, that a good point . I know I can measure the SR of the entire analog chain, but I also want to caracterise the intrinsic performance of the amplifier alone with the load. Best Regards!! IvoryDesigner
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yvkrishna Senior Member Offline Posts: 117	Re: Simulate slew rate of a fully differentiel amplifier Reply #3 - Mar 15^th, 2010, 6:45am Hi Ivory, apply a differential step at the inputs(each of half the magnitude) and measure slew at the diffferential o/p. Thanks, yvkrishna
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BackerShu

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Posts: 64

Re: Simulate slew rate of a fully differentiel amplifier
Reply #4 - Jun 28^th, 2010, 6:52pm

Hi Ivory!

This post may give you some reference if you still need it.
http://www.edaboard.com/viewtopic.php?t=373921&sid=4673be3c19446c2a6615a6baa5404...

By the way, I think sheldon's is much more proper to get the real SR spec of the OPAMP, since the exact environment of it can't be easily built, such as the C load, the influence of the clock signal if the circuit has one.

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Thanks and Regards!
BackerShu

https://www.linkedin.com/pub/shu-guanghua/26/b72/711

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