>
>> There is a tradeoff between speed and current consumption with the
>> resistor
>> divider, but that is no different than the tradeoff of what family gate
>> to
>> use for the other direction. My standard answer is 2K ohms in series
>> followed by 3.9K ohms to ground for 5.0V to 3.3V, but some cases may
>> require
>> lower values. 2Kohms // 3.9Kohms = 1.3Kohms, * 100pF = 130nS, so that
>> should be good for up to 2MHz square wave considering 100pF is very high
>> for
>> on-board traces.
>>
>> Do you have any fact-based objection or is your comment just silly
>> superstition?
>
>
> Where did you get 100pF in your calculations?  Is this just a conservative
> value you chose for a rough estimate?
>
>
>
> FJ

That brings up an interesting idea. How about treating the voltage divider
like a scope probe with a compensating capacitor across the top resistor.
Like with a scope, adjust the capacitor value until you get a square
waveform without overshoot. We have a resistive voltage divider in
parallel with a capacitive voltage divider.

Harold



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