Need op amp comparator advise

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I'm looking for a good comparator to work as a gate drive for a power
MOSFET. I used an LMV321 in my simulations, but I just found out the
lead time for these devices is about 2 months.
I'm looking at rail-to-rail voltage of 0 to 5V and I need something
with high gain so I can switch the MOSFET quickly. The comparator
should also be available in a DIP package. I can always try a u741, but
I'd like to know what else is out there.

Thanks in advance.

 

[John Jardine.]

I'm looking for a good comparator to work as a gate drive for a power
MOSFET. I used an LMV321 in my simulations, but I just found out the
lead time for these devices is about 2 months.
I'm looking at rail-to-rail voltage of 0 to 5V and I need something
with high gain so I can switch the MOSFET quickly. The comparator
should also be available in a DIP package. I can always try a u741, but
I'd like to know what else is out there.

Thanks in advance.

The LMV321 is an opamp and wimpy both as a comparitor or for driving a FET
gate.
Better would be a LM393 type comparitor with something like a 180ohm load
resistor. Basically, it's available everywhere, 8 pin dil, cheaper, more
precise, much faster and even has better rail to rail voltages.
john

 

[Rich Grise]

I'm looking for a good comparator to work as a gate drive for a power
MOSFET. I used an LMV321 in my simulations, but I just found out the
lead time for these devices is about 2 months.
I'm looking at rail-to-rail voltage of 0 to 5V and I need something
with high gain so I can switch the MOSFET quickly. The comparator
should also be available in a DIP package. I can always try a u741, but
I'd like to know what else is out there.

For heaven's sakes, use a real comparator! It shouldn't be hard to
google for a suitable one, but remember, typically a comparator has
an open-collector (or open-drain) output, so you need to pull up its
output. This could be a factor if you need fast switching - you have
to size the pullup resistor to give you a fast enough rise time to
your load, while not blowing out the output device.

I don't know any numbers off the top of my head, but you might try
http://www.google.com/search?q=comparator+IC

There are other ways of getting a fast rise time, of course, like
some kind of totem-pole, or a really fast opamp, or ...

Good Luck!
Rich

 

[Jamie]

I'm looking for a good comparator to work as a gate drive for a power
MOSFET. I used an LMV321 in my simulations, but I just found out the
lead time for these devices is about 2 months.
I'm looking at rail-to-rail voltage of 0 to 5V and I need something
with high gain so I can switch the MOSFET quickly. The comparator
should also be available in a DIP package. I can always try a u741, but
I'd like to know what else is out there.

Thanks in advance.

i've always liked the LM081/2/4 etc...

 

[Winfield]

I'm looking for a good comparator to work as a gate drive for a power
MOSFET. I used an LMV321 in my simulations, but I just found out the
lead time for these devices is about 2 months.
I'm looking at rail-to-rail voltage of 0 to 5V and I need something
with high gain so I can switch the MOSFET quickly. The comparator
should also be available in a DIP package. I can always try a u741, but
I'd like to know what else is out there.

Thanks in advance.

Best thing for the job might be an LM311 comparator. It's readily available
and costs almost nothing, but it has an open-collector output and is
active-low, though, so you'll need a pullup resistor capable of driving your
MOSFET.

Winfield