An ultra high slew rate recycling folded cascode OTA with 100-dB DC gain

Abstract

This article presents an operational transconductance amplifier (OTA) with enhanced transconductance and slew rate. High transconductance is achieved by implementing local common-mode feedback (LCMF) in a new path. This new path also is used in providing the current splitting technique. The slew rate is significantly boosted due to a new slew rate enhancement circuit, a new quasi-floating gate (QFG) circuit and two non-linear current mirrors. The advantage of the proposed OTA is that its large-signal and small-signal figures of merits are remarkably improved compared to previous works. The post-layout simulation of the OTA is in TSMC 180 nm CMOS process. Monte Carlo and corner analyses shows the robustness of the OTA with variations of process and mismatch.