Re: Buried Capacitance

[email protected]
Mon, 3 Jun 1996 11:41:41 -0400

On Jun 3, 6:43am, "John D. Allen" wrote:
> Subject: Re: Buried Capacitance
> An associate of mine evaluated it with a 3-D modeling package
> in about 1993. THe conclusion was that the noise level
> on the board was very significantly reduced - say from about
> 0.5V peak to 0.15 V peak or therabouts.
> So, you could removed MOST of the .01 caps from the board
> and most of the 0.1's also if you replaced them with larger bulk
> caps.

As compared to what? 6 mil verses 2 mil thick FR4? How much can be attributed
to increased mutual inductance? What was the frequency of the peak noise?
Did you consider charge depletion regions and radial power transmission time
domain effects?

... Rich Mellitz
> YMMV (Your mileage may vary) This was a SIMULATION.
> John Allen
> > From: "Don Abernathey" <[email protected]>
> > Date: Fri, 31 May