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INA250-Q1: negative pulse input at VIN, IN pins

Guru 20090 points
Part Number: INA250-Q1
Other Parts Discussed in Thread: INA250

Hello,

Are there any pulse negative pulse of absolute maximum ratings?
In the customer , there is the possibility that -0.7V pulse input at the VIN and IN pins.
I think that the -0.3V-GND is continuous input ratings.
I appreciate it if you have pulse ratings with time. (for example, -1V , 10ms etc..)

Best Regards,
Ryuji

  • Hi Ryuji,

    We do not have pulse ratings with time. The device analog inputs common mode maximum rating is -0.3V - GND to 40V. Anything outside this can damage the device.

    Editing my last comment: If they find a way to limit the input currents to 5mA they might be able to use our part. See the absolute values notes on the datasheet. 


    Regards

  • Hello Mayrim san,

    I appreciate your help.
    I have additional questions.

    (1)
    Could you please let me know the reason of 5mA?

    (2)
    Is there internal ESD protection diode at the +IN/-IN pins?
    I think that the GND-0.3V ratings is for the ESD protection diode.
    Are there ESD protection diodes both ends of internal shunt resistor 2mohm?

    We can add the external resistor for limiting input currents at the SH +/- pins and VIN+/- pins as Figure 36.
    Also there is the internal resister of Rint. (5kohm to 50kohm)
    However, we can't limit the input current at the IN+/IN- pins.

    Best Regards,
    Ryuji
  • Hello Mayrim san,

    Could you have any information of this issue?
    Our customer use current sense for pulse current.
    And the pulse voltage range is -1V(Low) , 35V(high) and current is 2.5A
    I would like to know that we can use this device for this application.
    What is the reason for the rating of -0.3 V even with the ± IN pins with integrated Shunt resistor?

    Best Regards,
    Ryuji
  • Hi Ryuji-san,

    I apologize for the delay, I was gathering more information to provide you with a better solution. 

    Pulses below ground to -1V will cause the ESD structure to induce extra current into the circuit and eventually cause it to fail. 

    In my previous post I said that limiting the current to 5mA could be a solution for this issue, but this is not the case for the INA250. My team just told me we have another customer that experience device damage with -1V spikes. 

    We are about to release a device with a wider Vcm that sounds like a great fit for this application. I can share all details offline. Please email me to mayrim.verdejo@ti.com

    Regards

  • Hello Mayrim san,

    I appreciate your support.
    I sent email to you.

    Best Regards.
    Ryuji