Richard Prosser wrote:
> I'm looking for a cheap quad opamp with the same pinout as the LM324.
> The killer is that I want one with a high input bias current.

That's really bad design.  You're not going to find a opamp that specifies a
minimum bias current.  If you need minimum current, put a resistor there.

> I can add additional pullup resistors but that would mean a pcb change
> and also (probably) retesting.

That's the way it goes.  That's the price of a design error getting this far
thru the process.  Either rework the existing boards or make new ones.
Maybe you can add the resistor elsewhere, but kludging this with a opamp
that appears to work from that production lot at your temperature is just
going to make things worse.

> So I'm looking for a cheap quad opamp ... with a minimum input
> bias current

Not gonna happen.  Go fix it the right way.


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