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How to use the disable pin of ADA4807-1

Category: Datasheet/Specs
Product Number: ADA4807-1

Hello

I use ADA4807-1. And I would like to enable this Op Amp always. So I use a 10kohm pull up resistor to connect to 3.3V, which is also the power supply of the Op Amp.

However, the Op Amp seems sink a lot of current. Then I change the resistor to 1Megohm. It seems the Op Amp works well.

I wonder why and How should I pull up this disable pin?

Thanks in advance!

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  • I don't understand. I pull up the disable pin with a 10kohm resistor. It seems the Op Amp is short circuit. But I change it to 1000kohm. It seems it could work. I don't understand which step is wrong? What resistor value I should choose if I want to tie it to supply voltage.

  • Hello ,

    On my reply above, I have recommended using a different voltage equipment/voltage source for the supply voltage pin and disable pin in order to isolate the problem. This means that you can still use a voltage similar to your supply voltage, but it has to be coming from a different voltage source. 

    When you've said that the op amp is sinking a lot of current when you used a 10kohm resistor for the disable pin, are you referring to the total current flowing on the supply pins and the disable pin (since you've said that they are using the same voltage source/equipment)? Or is it just the current flowing on the disable pin? What is the value of the current that sinks in the op amp?

    You've also said that when you pull up the disable pin with a 10kohm resistor, the op amp enters a short circuit condition. Can you share what output current have you measured in order to say so?

    May we also ask for the schematic of your circuit?


    Having the data above will really be helpful. Thank you.

    Best regards,
    Paul