I used a 74AHC74 running at 6V up to 200MHz. The first one ran hot and died
after some days, I replaced it and glued a small heatsink on top of it.
This one is still alive (for 2 years now, fingers crossed).
The 74AHC74 can be used as a divide-by-4 , normal 74HC or 74HCT dividers
can take over from there.
73, Rik ON7YD
PS : trying to push my luck I did run a 74AHC74 at 7V : that worked up to
230MHz but even with a heatsink the IC died after some minutes.
At 08:46 3/06/2003 +0100, you wrote:
I sucessfully use 74HC and 74HCT familty to at least 30 - 40MHz. It can
often
be pushed to just above 50MHz. If you want to got faster, the 74ACT
family can
be used as buffers to beyond 100MHz, but counters and shift registers in that
technology don't seem to go much beyond 80MHz in my experience
Andy g4JNT
-----Original Message-----
From: Steve McDonald [SMTP:[email protected]]
Sent: 2003/06/02 19:18
To: [email protected]
Subject: LF: 4060 Divider
I would like to use the M74HC4060 as a 'divide-by-64' signal source. Can
anyone tell me the upper limit for xtals that this chip can handle? My xtal
will be on 8.750000; I fear that the upper limit may be around 4-6 MHz?
Steve
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