Re: Clamping to Linear regulators

Thanks to everyone for their feed back. The 3.3V rail should have at least
20ma load on it all the time and I also have a 3.6V TVS diode on the rail
which I was hoping would prevent the voltage rising. Do you think this
would be ok or should I add the OP AMP?

Regards


AJ

"Mike Harrison" <mike@xxxxxxxxxxxxxxx> wrote in message
news:misg521vm3m4866646l1gfd7nj26grsrl0@xxxxxxxxxx
On Tue, 02 May 2006 15:48:01 GMT, "AJ" <itisme33@xxxxxxxxxxxxxx> wrote:

Hi,

I have a 3.3V linear regulator that I want to use to clamp 24V to via a
100K
resistor and a diode. Im pretty sure this is ok but just wanted to double
check. Does anyone have any feedback?



Depending on the load, it could potentially drag the 3.3v rail upwards.
A more universal solution would be to use an opamp set as a unity-gain
buffer, powered from the
supply into the 3v3 reg, with the input from the 3.3v supply.



.

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