A review of dual current-feedback amplifier techniques

Current feedback amplifiers (CFAs) offer excellent performance, especially in terms of slew-rate and bandwidth, and are now widely used particularly for video signal processing. However, some of the parameters of CFAs, such as CMRR, are disappointingly poor. Also, the topology, which is markedly different from the classical voltage feedback op-amp (VFA), means that the CFA cannot directly replace the VFA in a number of important application circuits, most notably the simple single amplifier Miller integrator. Monolithic dual CFAs can be configured to overcome some of the disadvantages of using a single CFA device, with net performance improvements and versatility approaching that of the VFA. In this paper some dual CFA amplifier techniques are reviewed and a clear insight into the operation and advantages is presented