Marechiare wrote:
> For Voltage Divider:
> Voltage divider is 2K + 3K.
> Power consumption factor 5V * 5V / 5KOhm = 5mW
>
> For FET & Resistor
> Power consumption factor 5mW, thus resistor is 3V * 3V / 5mW = 1.8
> KOhm

Exactly.  But to get the same speed, meaning same signal impedence, you
would need 1.2Kohms since 2Kohm // 3Kohm = 1.2Kohm.

> It's much better to synch to sharp falling edge
> as in the "FET + resistor" approach, than to fuzzy many factors
> dependent any edge as in "Voltage Divider" case.

Once again, there is no inherently better approach, so please stop making it
sound like yours is.  That is bad engineering.  What is better depends on
various factors of the design at hand.  In different situations the various
characteristics of any one approach will have different costs or advantages,
which change which approach will be better per situation.


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