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PGA207: Negative power rail to 0V, will it damage?

Genius 14359 points
Part Number: PGA207

Hi Team,

Good day. I have to confirm if shorting the negative power rail of this IA device to ground would result to damage?

I am thinking that it's fine though as normal op-amp will just clamp the output to minimum of 0V. I am having a hard time finding this information from its datasheet. Page 2 shows minimum power supply up to +/-4.5V.

May I know what's the maximum voltage limit for negative Vrail? Can you confirm? Thanks.

Regards,
Archie A.

  • HI Archie,

    The PGA207 can be damaged if the Absolute Maximum Ratings of page 3 are exceeded, for example, the device can be damaged if the supply voltage exceeds +/-18V. 

    Below is the PGA207 Absolute Maximum Ratings table:

    To answer your question, shorting the V- supply to GND will not permanently damage the device.  However, the device will not operate properly as it requires bipolar supplies to be properly biased and operate within its linear region.  As you have mentioned, the valid supply range for proper operation is from ±4.5V to ±18V per the datasheet.

    Thank you and Regards,

     Luis

  • Thanks Luis for your fast response.

    Regards,
    Archie A.

  • Just to clarify my query, I should asked "what is the minimum negative Vrail voltage?" (it's like the largest value, thus I said max) as I could see that snapshot from device info sheet. But you already confirmed it.

    Thanks again, Luis.

    Regards,
    Archie A.

  • Thanks Archie,

    Yes, you require at least a (V-) = -4.5V negative supply to operate the device, and the most negative supply allowed is (V-) = -18V.  The output voltage swing is delimited by the supplies.  The output swing is positive is specified to (V+) - 4V; and output swing negative (V-) +4V (minimum output swing range). 

    The common-mode input voltage range is approximately 2.3V below the positive supply to 1.5V above the negative supply. As a differential input voltage causes output voltage to increase, the linear input range is limited by the output voltage swing of the internal amplifiers A1 and A2.  This is shown in the plot of page 4 of the datasheet: Input Common-Mode Voltage Range vs Output Voltage.

    Thank you and Regards,

    Luis