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Design >> High-Power Design >> The source region is wider than the drain for powe
https://designers-guide.org/forum/YaBB.pl?num=1180515994

Message started by dandelion on May 30^th, 2007, 2:06am

Title: The source region is wider than the drain for powe
Post by dandelion on May 30^th, 2007, 2:06am

Hi,
I found for some MOS Tr at output power stage, the source diffusion region is wider than that of the drain. E.g., I ever saw for a class d power amp output stage, the width of source is ~2.1um while the drain is 1.1um.

Would anyone pls. tell me why?

Thanks

Title: Re: The source region is wider than the drain for
Post by krishnap on May 31^st, 2007, 2:47am

One type of devices used in the power Management blocks is extended drain
devices , in this case Drain will have additional area of diffusion compared to
the source. This terminal can handle high volatge/field and breakdown limit is more.
In this case source and drain dimensions are not the same.
Could you verify whether it is this type of device or something else?

Best regards,
Krishna