A novel design of low power and wide bandwidth operational transconductance amplifier using 0.35μm technology

Operational transconductance amplifier (OTA) is one of the most significant building-blocks of analog Very Large Scale Integration (VLSI). For high-performance analog circuit applications, the bandwidth and power consumption are the most important parameters to determine the performance of the OTA. In this paper a comparison of two architectures OTA based on the same topology is presented. Simulation results are shown for low power OTA and wide bandwidth OTA. The gain is 58 dB and 60 dB, slew rate is 7.7 V/μs and 70 V/μs, Cut-off frequency is 20 KHz and 250 KHz, settling time is 32 ns and 15 ns at ±1.5V supply voltage. Eventually we have succeeded in reducing the static power consumption to 0.036 mW for first version of OTA, and increase a Gain bandwidth to 126 MHz for second version of OTA.

I. Introduction

With the rapid development of computers and communications, wireless sensor networks [1]–[2] (WSNs), more and more chips are required to have small size, low-power and wide dynamic range [3]. Hence, low-power and low-voltage analog and mixed mode circuits are gaining importance. It is predicted that these circuits will require power supplies of 1.5V or less in future [4], [5].