Opamp supply

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AmiguelS

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Some opamps call for +-12V ( bipolar supply), while others call for +12V (unipolar).

The ones that need unipolar will not work with bipolar signals, unless you bias them. My question is, can you take a bipolar supply opamp and use a 0-12V supply and bias the input like you do with the unipolar supply opamps? Will it work properly, or will there be errors due to miss bias of the opamp internal transistors?
 
ANY opamp will work fine when its inputs are biased at about half the supply voltage which is 0V when there is a dual-polarity supply.
If the unipolar supply is 12V then bias the (+) input at 6V so the output can swing equally high and low.

With a unipolar supply then the input, output and feedback resistor to ground (if it is non-inverting) of the opamp need a series coupling capacitor.

Here are examples:
 

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Ok, thanks.
 
On the same components but different topic (didn't it was worth a new thread).
Whats the difference between the LT1028 and LT1128. From the datasheet the only difference is "LT1028 (gain of –1 stable)/LT1128(gain of +1 stable)", but I don't understand what they mean...
 
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