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Current sensor, 5 MHz -3dB bandwidth, 800V input Common Mode Voltage

Nitish Agrawal
Expert 1525 points
Other Parts Discussed in Thread: AMC1200, INA149, OPA365, OPA350

Hello,


Does TI have a current sensor (or current sense op amp) with 5MHz -3dB bandwidth and 800V input Common Mode Voltage?  I am trying to sense triangular shaped current at 500kHz (which has significant harmonics up to 5MHz).


Regards,

Nitish

  • 0
    TI__Expert 4595 points
    Hello Nitish,
    We will get back to you on Monday.
  • 0 in reply to Rabab Itarsiwala
    TI__Expert 4595 points
    Hi Nitish,
    I am moving your post to Precision Amplifier group and someone will assist you soon.
  • 0
    TI__Mastermind 25775 points
    Hello Nitish,

    None of our current shunt monitors, instrumentation amplifiers, or difference amplifiers have such large common-mode voltage ranges. However, there are a couple options that may be of interest:

    1) Low-side sensing. This places the common-mode voltage near 0V where you can use a number of devices, including op amps which would have a greater likelihood of meeting your BW requirement. Please let me know if this is feasible.

    2) AMC1200. Please take a look at the device data sheet. If you think this device will work in your application, please let me know and I'll move your post to the Precision Data Converters forum for further support.
  • 0 in reply to Pete%20Semig
    TI__Mastermind 25775 points
    Hello Nitish,

    I forgot to mention that the AMC1200 has a typical BW of only 100kHz.
  • 0 in reply to Pete%20Semig
    Expert 1525 points
    Hi Pete

    Thanks for your response. I have a couple of different requirements for common mode voltage: 450V and 800V.
    I note that TI doesn't have anything with CMR as high as 800V. What about 450V?

    I can explore low side sensing, if high CM voltage current sensors are unavailable in the 5MHz bandwidth. What device do you recommend for low side sensing? 100kHz b/w for AMC1200 won't work.

    Regards,
    Nitish
  • 0 in reply to Nitish Agrawal
    TI__Mastermind 25775 points
    Hello Nitish,

    With respect to instrumentation amps, current shunt monitors, and difference amplifiers the INA149 has the largest common-mode voltage range. You would need a large single supply voltage (e.g. 24V) to accommodate for 450V. Note that the BW is 500kHz (typical).

    For a low-side solution I recommend evaluating RRI/O op amps with low offset voltage, high slew rate, and of course high BW such as the OPA350 or OPA365.