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micro volt amplifier

i am working on project ecg mearsure and sending to pc wirelessly 

my problem is there is nothing output 

i am using circuit below


and is this diagram is correct in inverting amplifier configration


0 Votes


June 10, 2019 07:28

You say nothing is output, I presume that is after the x143 gain amplifier?
Is it 'stuck' at zero or at the supply rails?
Check the output amplifier first by injecting an input voltage, this may require removing the high pass filter.
The high pass filter will obviously remove DC and says 0.03Hz, how have you implemented that?
what have you used for the patient isolation protection circuit? Is that definitely allowing signal to pass?
This is the problem with block diagrams, they show the concept but not the details, so your circuit design and test method may help to provide the answer.

0 Votes

June 13, 2019 07:05

@Boss i am not a knowledge of analogue electronics this circuit i see on google how i design high pass filter for Arduino microcontroller and what is best op amp

June 17, 2019 07:10

@Kashifmirza it takes years of study and trying things to gain the experience, but there are many good sites and tools online. This tool from TI is good I suggest NOT making an ECG amplifier until you have much more experience and understand the safety issues and what can happen in the event of a fault - death is possible! Try an online analogue simulator as a starter, here are some to play with As for the op amp choice there are as you know millions to choose from, but a good old general purpose op amp is the TL072 has high impedance input with low bias currents and the NE5532 has lower noise. My 'stock' general purpose op amp is but that's because I'm often working on low voltage near DC signals.