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Simulators >> Circuit Simulators >> StrongArm Comparator Gain
https://designers-guide.org/forum/YaBB.pl?num=1272909056

Message started by Ruritania on May 3^rd, 2010, 10:50am

Title: StrongArm Comparator Gain
Post by Ruritania on May 3^rd, 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.

Title: Re: StrongArm Comparator Gain
Post by pancho_hideboo on May 3^rd, 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

Title: Re: StrongArm Comparator Gain
Post by Ruritania on May 3^rd, 2010, 3:25pm

pancho_hideboo wrote on May 3^rd, 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 3^rd, 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.

Title: Re: StrongArm Comparator Gain
Post by pancho_hideboo on May 4^th, 2010, 12:34am

Ruritania wrote on May 3^rd, 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-.