Cgs synth

>> Although, afaik, a TL072, unlike
>> the LM358, doesn't like going to rails. I'm not sure about positive
>> outputs, but the common mode voltage getting too close to the
>> negative rail of a TL072 can cause phase inversion and latch up. I
>> apologize if I sound overly critical, but for educational purposes,
>> I'm not sure why another comparator circuit was not used.

> Maybe the 358 would be better. I just had 072s, and they've worked on
> around 10 Bintics I've built.

When I built my Gate Sequencer I had problems using the LM358 as a
comparator. I think the transition time may be too slow. Instead of a
sharp trigger/pulse, there was a ramping up. This caused the CMOS chip
trigger/count to be very jumpy.


peng

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> When I built my Gate Sequencer I had problems using the LM358 as a
>comparator. I think the transition time may be too slow. Instead of a
>sharp trigger/pulse, there was a ramping up. This caused the CMOS chip
>trigger/count to be very jumpy.

LM358 are all over the place with regards to specs. Initially I was using a
very good batch when designing with them. Later I got a poor batch, realised
the problems and phased them out. For single rail supplies, perhaps the
MC34072 would do the trick if a TL072 won't.

Ken
_______________________________________________________________________
Ken Stone sasami@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

LT1013 is another good fast rail-safe opamp. MOTM standard for CV
processing etc.

hth