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High Voltage Comparator???

High Voltage Comparator???

High Voltage Comparator???

(OP)
I was wondering if anyone knows a company that produces a rail to rail comparator that can be supplied by at least 48V.  I would rather not use an op-amp because they are very very slow compared to a good comparator and the comparator has the open collector output that i need to decrease the components in my circuit.  Thanks for any help.

RE: High Voltage Comparator???

What are the specs you need ?

<nbucska@pcperipherals DOT com> subj: eng-tips
read FAQ240-1032

RE: High Voltage Comparator???

(OP)
I'm trying to make a basic switching power supply with a 48V supply rail-to-rail output comparator.  An open collector output would be perfect.

RE: High Voltage Comparator???

What wrong with using resistor dividers?

TTFN



RE: High Voltage Comparator???

Agree with IRstuff, resistive dividers on the inputs, and use the comparator output to drive a small MOSFET with open drain. That just about removes any real practical voltage constraints on either input or output. With a bit of detailed design it could be made quite fast.

RE: High Voltage Comparator???

(OP)
I am currently using a resitor devider-esque circuit with a FET.  We would really like to use a nice comparator to decrease board real estate and increase response time.  Comparators are in ns where the current system takes a couple us to become nice and stable.  Just a thought though.  These comparators would really help out for the next project.  I really need a comparator though, NOT and op-amp.  Thanks.

RE: High Voltage Comparator???

So why not use a comparator with a resistor divider?

Or, use high speed op-amps.  The typical switching power supply is only running in the sub-MHz range.

If you're that desperate for board space, then maybe you need to look at getting a custom hybrid.

TTFN



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