Electronic – Opamp stability given in not inverting configuration


If a datasheet (like AD828) says that an opamp is stable at Gain >2 (or reccomends to work with G>2, hence it is clearly not unity gain stable), what can we deduct about its stability in the inverting configuration at G=-1; G=-2 or G<<-2 (like in any transimpedance amplifier configuration)?
Is it always instable in the three above cases if not compensated?

Best Answer

Stability is a function of NOISE GAIN, not strictly the same thing as gain...

Noise gain follows the formula for the gain of a non inverting stage $$NG = 1 + Rf/Rg$$

For an inverting unity gain stage this will be 2, making the part stable in this configuration.