Design and Analysis of a 1.2V OTA-Based Active Filters in 45nm CMOS Technology

Operational Transconductance Amplifiers (OTAs) play a vital role in modern analog circuit design, offering a flexible and efficient approach to signal processing by converting input voltage into output current. Unlike traditional operational amplifiers (Op-Amps), which generate voltage-based outputs, OTAs provide current-based responses, making them highly suitable for applications requiring tunable gain and high-speed performance. This paper presents the design and implementation of an active filter using an OTA in 45 nm CMOS technology, optimized for operation at a nominal supply voltage of 1.2V. The proposed OTA-based filters, including Low-Pass, High-Pass, Band-Pass, and Notch Filters, exhibit low power consumption, high gain, and enhanced bandwidth, outperforming conventional designs. Simulation results indicate that at 1.2V, the OTA achieves a gain of 95.37 dB, a bandwidth of 34.88 MHz, and a power consumption of 5.72 mW. Additionally, the study examines the impact of varying supply voltage on power, gain, and bandwidth, highlighting key trade-offs. By leveraging the advantages of OTA-based design, this work provides a highly efficient solution for filtering applications in low-voltage, high-performance electronic systems, making it well-suited for communication systems, biomedical instrumentation, and RF applications.