Noise in AD624

Hello, my name is Eduardo Heredia and I am a student of Electronics Engineering at the National University of San Luis (Argentina). I am doing my final project; this is a digitally programmable signal conditioner from a plate with FPGA. The signal conditioner amplifies signals from 20uVpp to 1Vpp, for which use an AD624 instrumentation amplifier. The problem is that I have 12uVpp input noise with an input signal of 20uVpp and 20 kHz bandwidth. My question is, can generate noise of 12 uVpp in AD624?

Sorry for my English, I've only done two years of English course.

  • 0
    •  Analog Employees 
    on Sep 20, 2012 12:15 AM over 8 years ago

    Hello Eduardo,

    The answer to your question depends on many aspects, such as how you are measuring the noise, your test setup, your measurement bandwidth, the amplifier gain, and the behavior you observe at the output of the amplifier.  The best way to approach this is to begin by shorting the amplifier inputs and making sure the noise isn't coming from the source or getting picked up on the test leads. Also, in your picture the amplifier works in unity gain, which means you also have to make sure the noise is not just the noise floor from the measurement instrument.

    You can find plenty of resources on the web on this topic. One good starting point is our low noise amplifier page which you can find here:

    http://www.analog.com/en/content/over_low_noise_landing_page/fca.html

    Regards,

    Gustavo