Re: [SI-LIST] : implimentation of ground grid

About this list Date view Thread view Subject view Author view

From: Michael Nudelman (mnudelman@tellium.com)
Date: Mon Nov 06 2000 - 12:33:13 PST


Yaserh,

I could not fully understand this complex question of yours :-))) but:

The best results you get is from GND plane. This way you get the return
current flowing right under the trace in opposite directions to the GND
pin of the driver-IC.

If not, the GND grid will work (for not very high frequencies).

There are two rules:

1. Make the grid as dense as possible (though one IC per cell will do)
and
2. De-couple every corner of every cell. This way the return current
will have the shortest possible return paths, jumping through the
de-coupling caps.

Mike.

yaserh wrote:

> Hi, I need to know how i can make a gound grid to my PCB board, can
> any one give me a simple example of the ground grid. I read in the
> book of "noise reduction techniques, Henry Ott" that it's recomended
> to make a return path to each output from the IC to its gnd to avoid
> radiation from the PCB and the common mode problems.I need to ask for
> the case i use in my board the 74 series and every gate is connected
> to another IC have i need to connect the GND of the other IC's to this
> 74 series IC and each output is made parallel to the return, if i do
> this the denisty of the connection will be high has there is any other
> intermediate soloution and what is better. Waiting your replyWith my
> best regardsYasser El-haddad

**** To unsubscribe from si-list or si-list-digest: send e-mail to
majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE
si-list or UNSUBSCRIBE si-list-digest, for more help, put HELP.
si-list archives are accessible at http://www.qsl.net/wb6tpu
****


About this list Date view Thread view Subject view Author view

This archive was generated by hypermail 2b29 : Tue May 08 2001 - 14:29:59 PDT