I have thought about using one of the modern SM PLL chips such as the
National LMX2326 which can be progammed to give any division over a wide
range (you do need a controller though to drive it) - you can access the
main divider output directly and ignore the phase divider. These are widely
available and pretty cheap. I would think you could do one one these "dead
bug" with care, though they are SSOP. Of course if you are doing a PLL, why
not use the whole chip?
Richard
Harry (SM0VPO) wrote in message
...
Hi all,
I am having a spot of bother with prescaler chips. Basically I need to
find
one at the right price and availability. US$5 each is reasonable, but
where
from? Is there one available that is not obsolete?
I live in Sweden and my local component shop is ELFA (Swedens answer to
RS).
They don't sell ANY digital divider that operates above 50MHz, except for
the 74F163 and I cannot come up with a reliable interface circuit to
couple
an oscillator into it at over 100MHz.
I found the MB501 (MC12022, SP8704) but it is obsolete and cannot find a
reliable source. I bought a couple, but that source dried up. All I need
is
a divider chip that will accept a small signal up to 150MHz, is available,
cheap(ish) and will divide down to under 10MHz so that I can use CMOS to
process a synthesiser. A parallel-load synthesiser chip with in-built
150MHz
prescaler would do.
I have used "Teleport" to download over 50,000 pdf datasheets without any
luck. I have gone through most of them, but it takes a fair bit of time.
If
anyone has a helpful suggestion I would appreciate it.
BR from Harry - SM0VPO
http://w1.859.telia.com/~u85920178/
harryvpo (at) hotmail (dot) com