The LM7171 is a very high-speed, voltage-feedback amplifier (VFA). This device consumes only 6.5mA of supply current while providing a unity-gain bandwidth of 200MHz and a slew rate of 4100V/μs. The LM7171 also has other great features such as low differential gain and phase and high output current.

The LM7171 is a true VFA. Unlike a current-feedback amplifier (CFA) with a low inverting input impedance and a high noninverting input impedance, both inputs of a VFA have high-impedance nodes. The low-impedance inverting input of a CFA and a feedback capacitor create an additional pole that leads to instability. As a result, CFAs cannot be used in traditional op-amp circuits such as photodiode amplifiers, I-to-V converters, and integrators, where a feedback capacitor is required.