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INA597: differential amplifier with 2 op amp up to 2 MHz

Prodigy 230 points

Replies: 2

Views: 53

Part Number: INA597

Hello

i am looking to the layout attached. its a differential amplifier based on 2 op amp and a variable resistor to balance a DUT. Could you please advice a circuit and opamp that could do the function up to 2-3 MHz..

best regards

  • Hi Ahmed,

    Thank you for your post. The INA597 is a difference amplifier with high value input resistances. If you are trying to measure large currents, like in the ampere range, then a difference amplifier or an instrumentation amplifier will be okay.

    However, if the measured current is very small, like in the uA or mA range, you will need to take a look at an instrumentation amplifier.

    The INA821 may be a good option for you as it is a high precision instrumentation amplifier with 4.7MHz of bandwidth: http://www.ti.com/lit/ds/symlink/ina821.pdf

    -Tamara

  • In reply to Tamara M Alani:

    Dear Tamara

    thank you for your feedback, i tried to simulate waveform using TINA at high frequency 2MHz but i am getting strange output. my purpose is to balance R2 via R1 to get vout 1 =Vout2 for frequency omega (here 1000 Hz and 2 MHz). I also get an unusual peak at the onset. R2 will be devices with resistance in the range 20 - 90 ohms so i need to have R1 as a potentiometer to balance and cancel out the output. i added some capacitors at the power supply but it doesnt improve the waveform. any suggestions welcome.i attached some files if can help.

    Regards

    Ahmed

    1325.diff amp.TSC