An enhanced folded cascode OTA with push pull input stage

In this paper, a push pull configuration is proposed for the input stage of a folded cascode operational transconductance amplifier for enhancement of both gain and unity gain bandwidth. The proposed OTA and the conventional folded cascode OTA reported in the literature are implemented in UMC 0.18μm CMOS process and studied through simulation. From this, it is found that the proposed OTA has about 3dB higher gain and 100% higher unity gain bandwidth compared to the conventional OTA for same load and power consumption. This is achieved at the cost of reduction in the input common mode range by one threshold voltage V_TH. The proposed OTA can be used for designing high speed ADCs.