Joe,
     I think I will go with the 684. I'll start with a fixed display=20
time and just get the basic parts working. Clear the count, open the=20
gate, display the count, clear the count, and repeat forever. Then I'll=20
add the ADC with a pot to vary the display time and after that add the=20
ability to change the gating time. As I think of other functions I'll=20
add them.
Thanks,
rich,

On 7/18/2014 6:30 PM, IVP wrote:
>> Plus, the 628 doesn't have an ADC, only a comparator
> If continuously variable ADC usn't required and/or the application
> can use a pot divided into discrete segments, then the comparator
> can be used as a crude ADC by stepping through the internal
> reference voltage
>
> Joe

--=20
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