A CMOS digitally programmable OTA based instrumentation amplifier for EEG detection system

In this paper, the instrumentation amplifier (IA) based on digitally programmable operational transconductance amplifier (DPOTA) is designed for EEG detection system. The proposed IA consists of DPOTA cascaded with a digitally programmable gyrator. The digital control circuit of DPOTA is done using current division network (CDN) for 4-bit code word. PSpice results are done using 0.25μm IBM CMOS process. The IA provides moderate gain (6.43dB-29.78dB), and consumes power by 13.57μW with input referred noise. Higher gain is achieved by two cascaded stages of this IA providing more programmable gain (13.81dB-60.15dB), input referred noise of and power dissipation of 27.4μW. These results show the ability of this IA to be used as first stage in EEG system.