A 1-V, 5 μW, Atto Current Bulk-Driven CMOS Based Operational Transconductance Amplifier for Biosensor Applications

There is an advent need in health industry, for an Implantable Medical Device (IMD) withlower power consumption, noise and area as much as possible, which aims at extending the life-span of the device by enhancing the performance of battery to avoid additional surgery and does not affect the tissue cells. The existing IMD detects a single disorder and consumes high power resulting in need of replacement within a period of time. Furthermore there is a sheer need to reduce the noise factor to achieve an uninterrupted signal. This paper proposes a novel Operational Transconductance Amplifier (OTA) which is used in the biosensors of IMD. The proposed OTA is designed in a 0.18 μ m CMOS (Complementary Metal Oxide Semiconductor) technology, the operational frequency is in the range of 0.36 Hz to 50 KHz and capable of measuring the gain in 60 dB. It consumes a negligible amount of (5 μ W) power per OTA from 1-V single power supply and achieves minimal input referred noise of 1.24 μ V rms , which is highly acceptable for biosensor used in IMD. The post layout simulation of the proposed integrated circuit has been performed successfully.