Mounting electronics circuits on a plastic flexible substrate are pertinent for biosensing applications due to their resilient nature, minimal processing conditions, lightweight and low cost. Organic Field-Effect Transistors (OFET)-based amplifier for flexible biosensors have been proposed in this paper. To design flexible biosensing circuits, Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) with Polycyclic Hydrocarbon is a suitable choice. It is a big challenge to build an organic circuit using graphene electrode due to its poor performance of [Formula: see text]-type OFET, therefore it is advisable to use Pentacene as [Formula: see text]- and [Formula: see text]-type Organic semiconductors. Pentacene being one among the foremost totally investigated conjugated organic molecules with a high application potential because the hole mobility in OFETs goes up to 0.2[Formula: see text]cm2/(Vs), which exceeds that of amorphous silicon. In biosignal process, the first and most important step is to amplify the biosignal for further processing. Operational Transconductance Amplifier (OTA) plays an essential role in biological signal measuring instruments like EEG, ECG, EMG modules which measure the heart, muscle and brain activities. The OTA designed using this OFET is adaptable for flexible sensor circuits and also it derives the transconductance of 67 which is similar to silicon OTA. The amplifier designed here gives unit gain of 42[Formula: see text]dB with a frequency of 195[Formula: see text]Hz which is suitable for low-frequency biosignal processing applications.
Low Frequency Filter Design using Operational Transconductance Amplifier