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Design >> Analog Design >> on 0.13um tech.
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Message started by ontheverge on Oct 5^th, 2010, 4:50pm

Title: on 0.13um tech.
Post by ontheverge on Oct 5^th, 2010, 4:50pm

Hi,

I was designing an folded cascode op-amp in 0.13um technology, the single stage gain requirement dictates that channel length to be larger than 0.35um (with specific circuit architecture), if the way i designed it was right, does that mean the technology was wasted?

thanks,
Steve

Title: Re: on 0.13um tech.
Post by AnalogDE on Oct 6^th, 2010, 9:00am

I'd recommend sizing the cascodes using minimum channel length.

Title: Re: on 0.13um tech.
Post by raja.cedt on Oct 6^th, 2010, 7:09pm

hi steve,
what do you mean by wasted, mainly these process nodes are highly digitally biased..so you don't get good gds, in fact there are people who design analog design circuits with 1u channel length also. so what i my suggestion is try to use min-length devices wherever possible like cascode devices.

Thanks.

Title: Re: on 0.13um tech.
Post by ywguo on Oct 6^th, 2010, 7:47pm

Hi Steve,

There must be more specs than the DC gain. So your choice of the channel length is a compromise of all specifications. Does the current channel length result in a good balance between power, speed, gain, area, mismatch, noise, and so on? If the answer is YES, it's fine. Anyway, the deep sub-micron technology is optimized for digital design, not for analog.

Best Regards,
Yawei

Title: Re: on 0.13um tech.
Post by love_analog on Oct 11^th, 2010, 6:10am

This is not wasted. What it means is that you are using a larger Length device to get higher Rout.

Title: Re: on 0.13um tech.
Post by Alexandar on Oct 13^th, 2010, 7:54am

If you are using the 3.3V devices, a gate length of 0.35 um is quite minimal.