Calculate op-amp gain and check it against the gain-bandwidth product.
Gain and bandwidth trade directly against each other: their product is fixed by the device. A non-inverting stage cannot have a gain below one, while an inverting stage can attenuate. A 1 MHz op-amp configured for a gain of 47 has only about 21 kHz of bandwidth, which catches out many first designs.
Op Amp Gain
Inverting: A = −R_f ÷ R_in; non-inverting: A = 1 + R_f ÷ R_in; bandwidth = GBW ÷ gain
Inverting: A = −R_f ÷ R_in; non-inverting: A = 1 + R_f ÷ R_in; bandwidth = GBW ÷ gain Gain and bandwidth trade directly against each other: their product is fixed by the device. A non-inverting stage cannot have a gain below one, while an inverting stage can attenuate.
A 1 MHz op-amp configured for a gain of 47 has only about 21 kHz of bandwidth, which catches out many first designs.
This calculator takes 4 inputs: Input resistor, Feedback resistor, Gain-bandwidth product, Configuration. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.