Post Go back to editing

AD5522 Force 0.1 V

Category: Hardware
Product Number: AD5522

HI

Because we need a 80mA current source, so place a 12.5ohm on Rsense.

And try to set a test environment as below.

(1)Force 0.1V  , measure I (Selected Current Range:±external current range.)

I try to short test point with ground point and then expected value is 80mA.

Unfortunately, value is around 2.5mA.

(2)Force 5V and connect 500ohm, current is 9.6mA.

Do you have any advise to me?

Parents
  • Hi, Kentlle.

    It is correct that if you want to utilize the full scale 80mA current range, you must put 12.5ohm resistor as an Rsense. However, there are a few things I would like to know to help you better.

    1. In your first condition, what is your load?
    2. Still in the first item, what test point are you shorting to GND? I am not sure of what we would like to achieve through this, so it will help if you can elaborate more on what you are trying to do.

    For your second item, you are supposed to measure 10mA when forcing 5V to a 500-ohm load. You are measuring 9.6mA which is pretty close. But if we want to achieve current even closer to 10mA, it will help to check the tolerance of the load as well as the calibration settings of AD5522.

    Thanks,
    Mac

  • Dear Mac,

     Thanks for prompt reply.

    1. In your first condition, what is your load?

        Just a wire to short ground...  We design a relay board that can switch channel.

       Apply in IC test. Set a 0.1V on power pin to detect short or not short with other pins.

      Take pass sample to test, current is 2.3 mA  and take fail sample to test, current is 2.7mA.

      We use another tester to test these sample. Pass sample is 7mA and fail sample is 50mA above.

    So we think AD5522 driver ability is not enough at 0.1V condition.

Reply
  • Dear Mac,

     Thanks for prompt reply.

    1. In your first condition, what is your load?

        Just a wire to short ground...  We design a relay board that can switch channel.

       Apply in IC test. Set a 0.1V on power pin to detect short or not short with other pins.

      Take pass sample to test, current is 2.3 mA  and take fail sample to test, current is 2.7mA.

      We use another tester to test these sample. Pass sample is 7mA and fail sample is 50mA above.

    So we think AD5522 driver ability is not enough at 0.1V condition.

Children