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Design >> Analog Design >> Process independent Bias Current Generation
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Message started by papodu on Jun 24^th, 2010, 11:40pm

Title: Process independent Bias Current Generation
Post by papodu on Jun 24^th, 2010, 11:40pm

What is the best way to generate a process independent bias current, given that extenral resistor is not available and very accurate bandgap reference is available( untrimmed 6sigma of 2.5%).
Thanks for any help.

Title: Re: Process independent Bias Current Generation
Post by raja.cedt on Jun 28^th, 2010, 2:06am

hi,
where you need such high accuracy?

Thanks.

Title: Re: Process independent Bias Current Generation
Post by papodu on Jun 28^th, 2010, 2:25am

I need bias current accurate to +/- 10% .. and i have bandgap ref of 2.5%6 sigma accurate.

Title: Re: Process independent Bias Current Generation
Post by Vladislav D on Jun 28^th, 2010, 11:32am

despap wrote on Jun 24^th, 2010, 11:40pm:

I think, no ways to design current source independed on corners without trimming or offchip resistors. Furthermore, I don't see a reason to do such sources. It may be even dangerous if all devices go in one direction due to a corner,whereas a current source keeps a constant value of current. A circuit might leave the "right" bias. What really need is to keep low variations due to statististical mismatches.