Comparison between Miller integrator cells using VOAs and CFOAs

The current feedback opamp (CFOA) emerged as a high-speed alternative to the conventional voltage operational amplifier (VOA) and since its introduction a wide spectrum of applications have been proposed, also in the filters area. However, no effort has been aimed to demonstrate under what conditions improvements are achievable and to outline eventual limitations. At this purpose, the paper presents an accurate performance comparison of Miller integrator cells based on CFOAs and VOAs. Basic inverting and noninverting integrator structures are analyzed and simulations performed with transistor-level circuits are also given.