I have a question about the power supply to an op amp.

My op amp requires a Vcc of +/-5V. Now fr the +5V part, I am planning to use a 78L05 voltage regulator. But I am pretty much unsure what I need to do for -5V.

I could probably use 79L05 and get -5V directly.

Or as a friend suggested, I could use a pump converter like MAX660 to invert the voltage. But I was looking thru the specs for MAX660 and noticed that it should invert the voltage fine, but the input current is of the order of a few uA. My 78L05 produces +5V at 100mA.

So my question is that will the inverting of +5V (100mA) by using a MAX660 chip fry the MAX660 chip itself?

Any help is highly appreciated.

Thanks

 

no it won't
but negative regulators are easy

 

no it won't
but negative regulators are easy

Thanks R!f@@. I had the same feeling and in fact after I posted here, I realized that it should not matter. But a confirmation from an expert like you really puts the nail in the coffin. And as you suggested, I will use the negative regulator to keep my stuff simpler.

 

me no expert
me simple guy

 

But I was looking thru the specs for MAX660 and noticed that it should invert the voltage fine, but the input current is of the order of a few uA. My 78L05 produces +5V at 100mA.

So my question is that will the inverting of +5V (100mA) by using a MAX660 chip fry the MAX660 chip itself?

I read the MAX660 data sheet as giving the maximum output of 100 ma. If the load is only one op amp, the 78L05/Max660 should work fine.

The question comes from this statement -

I could probably use 79L05 and get -5V directly.

If that means you have a negative voltage source, then the 79L05 will be superior to the MAX660.