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StrongArm Comparator Gain (Read 9797 times)
Ruritania
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StrongArm Comparator Gain
May 03rd, 2010, 10:50am
 
Hi,

For the conventional StrongArm comparator (see figure attached below), we know that shortly after the rising edge of ph1, there's an amplification stage between the input (Vin+, Vin-) and output (vo+, vo-), before the regeneration takes over the operation. My question is how to simulate or predict this gain in the simulator, for example, spectre or spectreRF?

Thanks.
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pancho_hideboo
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Re: StrongArm Comparator Gain
Reply #1 - May 3rd, 2010, 11:19am
 
I can't find out any design issue in your post.
Your question is no more than usage of specific vendor's simulator.

http://www.designers-guide.org/Forum/YaBB.pl?num=1245967593/2#2

analyses -> tran -> option -> actimes = 100n
acname = ac

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Ruritania
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Re: StrongArm Comparator Gain
Reply #2 - May 3rd, 2010, 3:25pm
 
pancho_hideboo wrote on May 3rd, 2010, 11:19am:
I can't find out any design issue in your post.
Your question is no more than usage of specific vendor's simulator.


Sorry that I might have posted this at the wrong place. I supposed that people working on High speed I/O design may come across with the same issues.

pancho_hideboo wrote on May 3rd, 2010, 11:19am:
http://www.designers-guide.org/Forum/YaBB.pl?num=1245967593/2#2

analyses -> tran -> option -> actimes = 100n
acname = ac



I tried, but didn't work (the output gain is like -100dB, obviously not right). Is it because of the dynamic characteristic of this circuit?

Thanks.
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pancho_hideboo
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Re: StrongArm Comparator Gain
Reply #3 - May 4th, 2010, 12:34am
 
Ruritania wrote on May 3rd, 2010, 3:25pm:
I tried, but didn't work (the output gain is like -100dB, obviously not right).
Do you set proper time for "actimes" ?

Try to vary "actimes".
You can set time array for "actimes".

actimes=[...] ; Times when analyses specified in acname array are performed.

Show me your netlist regarding signal sources and tran statement.

You must not set large signal sinusoidal for Vin+ and Vin-.

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