Currently using crystal.
Will almost certainly go to resonator at best.
Will examine possibility of RC once all other considerations are
obvious - these often pop up unextepctedly during development despite
best efforts to "design" from scratch.
With sigma-delta the short term clock stability (over one conversion
cycle of around 10 milliscecond) is all that matters.

RM


-----Original Message-----
From: Graham Daniel <g.daniel.invent.design@xtra.co.nz>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Thursday, July 15, 1999 7:00 PM
Subject: Re: Sigma Delta Converter


>Russel,
>are you using resonator,xtal or RC clok on yaw zillllog ?
>
>I would assume that PSU voltage fluctuations will significantly
affect
>timing accuracy in RC mode, possibly to a lesser extent also with
>resonator. This of caws wood spoil yaw S.D.G. rdng.
>
>rgds,
>G.D.
>
>--
>Steam engines may be out of fashion, but when you consider that an
>internal combustion engine would require recovery of waste heat by
>transfer just before top dead centre then fashion becomes rather
>redundant, USE STRATIFIED HEAT EXCHANGERS ! and external combustion.
>
>You heard it first from: Graham Daniel, managing director of
Electronic
>Product Enhancements.
>Phone NZ 04 387 4347, Fax NZ 04 3874348, Cellular NZ 021 954 196.
>