Design of Optimal Amplifier for Wearable Devices

The demand for health-monitoring wearable devices is increasing worldwide among scientists and clinicians. Low-power, low-voltage and low-noise attributes are important concerns that need to be addressed in circuits used for continuous personal health monitoring applications, to achieve long battery life. So the need for low-power low-voltage bio-amplifiers is increasing. These amplifiers receive the bio-signals through the bio-sensor, attached to the patient. Thus the amplifier acts as an interface to the wearable device and amplifies the difference between the two input signals from the bio-sensor. So, it is an important block at the front-end of the device. In this paper, a low- voltage OTA used for the bio-potential signal acquisition system is presented with MOS-Bipolar pseudo resistor configuration. Super source degeneration and bulk driving technique operated in sub-threshold region to achieve low-power and low- voltage criteria. The designed bio-amplifier is capable of amplifying the bandwidth range of 0.5Hz to 300Hz bio-potential signals like ECG, EEG and EMG etc.