Design of Low Power Low Voltage Bulk Driven Operational Transconductance Amplifier (bd-ota)

Operational Transconductance Amplifier (OTA) is one of the most significant building-blocks in integrated continuous-time filters. Here we design Low Power Low Voltage Bulk Driven OTA with a new concept of high-linearity OTA with controllable Transconductance is proposed. The OTA is simulated in a standard TSMC 0.18 mm CMOS process with a 0.6 V supply voltage. 1. INTRODUCTON Low-voltage (LV) and low-power (LP) CMOS circuits have received considerable attention recently due to several reasons: a) Many of today's integrated circuit (IC) applications such as portable communication, remote computing and wireless communication systems require high performance IC's that operate under low supply voltage and consume low power. b) With the increasing circuit density in VLSI, the requirement of low cost fabrication demands circuits with low power consumption [1]. c) The use of scaled down technologies has imposed a reduction of supply voltage. The OTA is an amplifier whose differential input voltage produces an output current. Thus, it is a voltage controlled current source (VCCS). There is usually an additional input for a current to control the amplifier's transconductance. The OTA is similar to a standard operational amplifier in that it has a high impendence differential input stage and that it may be used with negative feedback. Portable electronics with low-voltage operation finds big markets [3]. However, the threshold voltage is not reduced proportionally with the supply voltage. Thus, the threshold voltage is becoming a restraint for many analog circuits. Some special techniques are used to overcome the size of the threshold voltage, e.g. floating gate