Question

You measure the voltage difference between two ECG electrodes placed on your right arm and left leg (lead II). You use an instrumentation amplifier with a differential gain of 75 and a CMRR of 80 dB. The common-mode voltage, present at both of your amplifier inputs, is 1.2 V. Your ECG waveform varies between -2.5 mV and +2.5 mV. What are the bounds of the output voltage of the instrumentation amp (i.e. the min and max voltage)? Give your answer to 4 decimal places.

Answer 1