The instrumentation amplifier demonstrated below is to be used such as the front-end phase of an ECG recording system. The ECG electrodes consist of a nominal impedance of 20k, along with a mismatch of up to 5k among them. All of the operational amplifiers include a minimum CMRR of 70dB and all resistors in the amplifier encompass a ±5% manufacturing tolerance. Define the overall CMRR of the recording system and find the percentage error within the measurement of an ECG signal containing amplitude of 1m Vptp within the presence of common-mode mains interference containing amplitude of 15mVrms.
