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AD8009 Single Power Supply

I am tring to build an amplifier circuit by using AD8009 with its single power supply. However, when I applied +10V to VS+ and GND to VS-, it seems the amplifier didn't work. The output current of my digital power supplier is about 0.  Can someone help me figure out the problem? And Is there any example of how to supply for AD8009 using single power supply?

Thanks in advance.

Quentin

  • Hi Quentin,

    Can you provide your circuit diagram for us to analyze the issue thoroughly?
    Also, can you share the desired application for AD8009? This way we'll be able to suggest or give better inputs based on the requirements.

    Thanks a lot Quentin.

    Best Regards,
    Dann

  • Hi Dann,

    Thanks very much for your reply.

    Please find the attached circuit diagram we are using now. The photodiode was open when I turn on the power of AD8009 and the current through the power was about zero. It seems I should to arrange suitable input and output resistor so that I can test the amplifier correctly.

    When I change the circuit diagram into the following one, it seems the amplifier work now with the power current of 68mA.

    In the datasheet of AD8009, some performance parameter with +5V power supply are listed. But I didn't find related circuit diagram. Could you help to provide it?

    Our application is to amplify the fast signal generate by the photodiode. It works fine with dual power supply, now we want to change the power supply into single. 

    Thanks again for your help.

    Quentin

    Best Regards

  • Hi Quentin,

    Based on your circuit, since you're using a single supply operation (0V to 10V) you can refer to AD8009 specifications at Vs = ±5.

    Also, just a few notes on your AD8009 configuration, I noticed that you're using a 500 ohm feedback resistor which is not recommended on the datasheet. AD8009 is a current feedback amplifier and is limited on the feedback resistor values in order to maintain the bandwidth and stability of the amplifier. On the spec table of AD8009,there are recommended Feedback resistors on the two different package at different gains(+1, +2 and +10).
     
    For the circuits, I have a few clarification.
    Are you trying this on an actual circuit? Is it on breadboard or vector board?
    For the first circuit, you should be measuring the quiescent current of the amplifier upon power up which is typically at 14mA for the AD8009. Please make sure you're able to connect it properly.


    Also, may I know your specific photodiode and the Vbias you're using? This way I'll be able to assess the actual operation of the amplifier.

    With regards to the related circuit diagram.
    In photodiode applications, Transimpedance configuration is usually used, please refer to these articles for the detailed explanation of the circuit designs.

    https://www.analog.com/en/analog-dialogue/articles/compensating-current-feedback-amplifiers.html
    https://www.analog.com/media/en/technical-documentation/technical-articles/S54_EN-Circuits.pdf

    If you have clarifications please feel free to ask.
    Thanks a lot Quentin.

    Best Regards,
    Dann

  • Hi Dann,

    Thanks very much for your reply.

    We modified the circuit configration as the following one, and now it works fine.

    It is an actual circuit on printed circuit board. The photodiode is an APD, the Vbias is 28V. The photodiode is work on geiger mode.

    If you have any comment on this configuration, please let me konw.

    Thanks,

    Best Regards

    Quentin