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Is an OP07 unity gain stable ? I am powering it with a +/- 5V supply. I am using it to buffer a DC signal which varies slowly.

Most of the modern Op-amps have their datasheets mentioning them explicitly as unity gain stable,but nothing like this is mentioned in the OP07 datasheet.

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it have already used as a voltage follower, so the answer is yes it does. From a application note. – sandun dhammika Apr 29 '12 at 20:37

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Yes, it is unity gain stable. Figure 18 shows the curve for 0 dB of closed-loop gain vs frequency.

Closed-loop gain vs frequency

An interpretation of this diagram: The vertical axis is in dB. For example, for a closed-loop gain of 0 dB (or 20 dB, or any other gain in the diagram), the opamp is not unstable at any frequency. The curves just tell you that the closed-loop gains (for those gain settings) roll off / decay like that, with frequency. The higher the gain, the lower the bandwidth, so that the product gain*bandwidth is constant. It may be assumed that it is stable for G=1 (0 dB) because the datasheet specifies the behavior for that gain (it shows the curve for it). If it was unstable for G=1, you wouldn't see a curve for it, in that figure.

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Does this mean eg. the opamp becomes unstable at a gain of 20,above30kHz ? – EmbSysDev Apr 30 '12 at 7:43
@EmbSysDev The vertical axis is in dB. And no, for a closed-loop gain of 20 dB, the opamp is not unstable at any frequency. The curves just tell you that the closed-loop gains (for those gain settings) roll off / decay like that, with frequency. The higher the gain, the lower the bandwidth, so that the product gain*bandwidth is constant. I said it is stable for G=1 (0 dB) because the datasheet specifies the behavior for that gain (it shows the curve for it). If it was unstable for G=1, you wouldn't see a curve for it, in that figure. – Telaclavo Apr 30 '12 at 10:46

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