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LM193 Comparator proper output state even if the common mode range is exceeded on one input?

PaulSchoenke
Genius 3290 points
Other Parts Discussed in Thread: LM193, LM2903, LM339, LM393, LM324, LM358

Hello:

The datasheet for LM193/293/393/2903 has the following footnote for the LM193/293/393:

 

The same datasheet has the following footnote for the LM2903/2903A:

 

My question is…

Is it true that only the LM193/293/393 will provide a proper output state even if the common mode range is exceeded on one input, or will the LM2903/2903A also provide a proper output state even though that footnote doesn’t explicitly state it?

My application could allow for the non-inverting input to exceed the VCC level, so I need to make sure that the output state is correct and I would like to use the LM2903. 

Best regards,

Paul

  • 0
    TI__Guru**** 150976 points

    Hello Paul,

    The footnote does apply to all the devices in the data sheet.

    All the devices in the LM393, LM339, LM358 and LM324 data sheets can provide a proper output when one input is in common mode range and other input greater than VCC (up to max VCC rating)

    For future data sheet revisions I am considered this text be put on the front page.

    ·   Either input (not both) can exceed common mode range beyond VCC (up to max rated VCC) while maintaining a valid output state.

    Do you consider this statement clear and concise?

    Regards,
    Ron Michallick

  • 0 in reply to Ron Michallick
    Genius 3290 points

    Thanks Ron!

    I shared this with my customer and his input was as follows:

    I might revise the below statement (assuming what I add is true):

    ·   Either input (not both) can exceed common mode range beyond VCC (up to max rated VCC) while maintaining a valid output state.

    to read:

    ·   Either input (not both) can exceed common mode range beyond VCC (up to max rated VCC) while maintaining a valid output state, provided the other input remains within the common-mode range.

  • 0 in reply to PaulSchoenke
    TI__Guru**** 150976 points

    Paul,

    I was hoping the (not both) implied the same as red addition. Thanks for the feeback.

    The red addition is accurate.

    Regards,
    Ron Michallick