Designing of Current Mode Instrumentation Amplifier for Bio-signal Using 180nm Cmos Technology

In this paper we have describes the design of current mode instrumentation amplifier (CMIA) for bio-signal Acquisition system. The current mode instrumentation amplifier technology is based on voltage mode operational amplifier (op amp) power supply current sensing technique. There are two design challenges of this topology. First one is the Op amp mismatch and second is precise current mirrors. A new low-voltage single-power high CMRR and PSRR instrumentation amplifier is developed for medical applications. This proposed circuit uses a new structure to solve the general circuit’s problems. The overall proposed circuits by virtuoso 6.1.5 using UMC 0.18um CMOS technology achieve a very high CMRR 130dB up to 87 HZ and higher than 100dB up to 10k Hz and PSRR 110 dB up to 1k Hz and 39 dB closed loop gain at 1.8V single power supply Keywords— Sample and hold (S/H), ADC, PSRR, CMRR, gain bandwidth product (GBW), trans conductance