Now I made a circuit to measure ECG based on the AD8236. I followed the example in the AD8236 manual as shown below.
But when I test with electrodes connected to the human body, I found the output of AD8236 remained 2.5v. I cannot see the ECG waveform at the output of AD8236. When I removed the pull resistors at the inputs of AD8236, I can see the ECG signal at the output of AD8236 by the oscilloscope. Does that normal? Did I make any mistakes? Appreciate your help.