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TLV1702: Power Supply Glitch

Kazuki Itoh
Genius 11600 points

Part Number: TLV1702
Other Parts Discussed in Thread: TLV1701

Hi team,

I have a question about the power supply for the TLV1702AIRUGR comparator.

In my customer's application, V+ = GND and V- = -5V.
However, there is a possibility that +0.3V to +0.5V may be applied to V- for a short time before the -5V is applied.

I could not determine from the datasheet whether this is acceptable.
Please let me know if this could cause any problems.
If so, my customer will need to consider countermeasures.

Thank you for your assistance.

Best regards,
Kazuki Itoh

  • +1
    TI__Guru 68446 points

    Hello Kazuki-san,

    This will cause the substrate diode and ESD protection to start conducting, causing high currents (mA levels).

    The TLV1701 datasheet does not specify a lower supply Abs Max supply value, but usually it is -0.3 to -0.5V.


    The "power clamp" will start conducting. (The TLV1701 does not have Power On Reset - so ignore that). The current needs to be limited to 10mA or less.

    I would recommend that they place a Schottky diode between V- and GND to clamp the positive voltage to < 350-400mV. This would also benefit all the other devices connected to V-.

    If they are really concerned, they could place a resistor in series with the V- supply pin to limit the reverse current. Lets say 100 ohms. Since this is a low power open drain device, the supply current does not change much. 100ohms*100uA = 10mV drop. A larger-than-normal bypass capacitor (~1uF) should be placed directly at the V- terminal to ensure a stable supply.