Newsgroups: comp.robotics
Path: brunix!sgiblab!swrinde!cs.utexas.edu!howland.reston.ans.net!torn!newshub.ccs.yorku.ca!newshub.ariel.cs.yorku.ca!cs911225
From: cs911225@ariel.cs.yorku.ca (KEN E WILLMOTT)
Subject: The penultimate 40Khz generator?
Message-ID: <CKCJKD.DxK@ariel.cs.yorku.ca>
Sender: news@ariel.cs.yorku.ca
Organization: York University, Dept. of Computer Science
Date: Fri, 28 Jan 1994 15:41:01 GMT
Lines: 21

Hi,

Regarding a simple way to generate a stable 40Khz signal, I
think I have come up with a way that is straightforward
(i.e. does not have an analogue network to confuse things)
and inexpensive.

Get a 5.12Mhz oscillator module (not just a crystal). These
run off of 5 volts, and contain all the messy analogue circuits
that are needed to oscillate. They cost the same a crystal, about.

Feed the output signal into any binary divider chain. I suggest
the HC4060, a high speed CMOS version of the 4060 osc/divider.
With this part, you do that by feeding the 5.12Mhz signal into
pin 9. A bonus is that you get buffered clock signals at pin 10
and pin 11 (one is the compliment of the other). This could be
handy for any design that needs a CPU clock at that frequency.
Don't forget to ground the reset pin, or the counter won't work.

	-Ken Willmott

