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TS12A12511: What happens when the supply voltage is lost

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Replies: 3

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Part Number: TS12A12511

I'm looking for a switch with 12V SUPPLY, RDSON<10 Ohm and defined status when supply voltage is lost.

We found the TS12A12511.  However there is no information in the datasheet about the status when supply voltage is lost.

Do you have recommend a different part? 

What happens with TS12A12511 when supply is lost?

  • Hello,

    What exactly do you mean by "defined status" when supply voltage is lost? Are you expecting to have a signal present at the input/output pins while VCC=0V?

    For TS12A12511, according to absolute maximum ratings, if VCC=0V and a voltage greater than 0.5V is present at the I/O pins, the internal ESD protection diodes will be forward biased and the device/system may be backpowered.

    What is the I/O voltage of the switch during normal operation? I would like to confirm that you need a supply voltage of 12V.

    Thank you!

    Regards,
    Kate

  • In reply to Kate Dickson:

    Thanks for your feedback. Here the different scenarios:

    COM pin=5V

    IN Pin=5V

    V+= floating

    V-= floating

    What happen on NC and NO in this case?

     

    COM pin=5V

    IN Pin=0V

    V+= floating

    V-= floating

    What happen on NC and NO in this case?

    COM pin=5V

    IN Pin=0V

    V+= floating

    V-= GND

    What happen on NC and NO in this case?

  • In reply to Manuel Infante:

    Hi Manuel,

    Thank you for the clarification. 

    Floating supply pins will create an undefined state within the switch, so leaving supply pins floating is not recommended when you expect a signal to be present on the I/O pins. 

    Powered-off protection is a feature that ensures that the switch is in the high-impedance state when VCC=0V, but this only offers protection when VCC=0V and NOT when the supply pin is floating. We do not currently have any switches of this configuration & 12V supply with powered-off protection. Since the I/O signal voltage is 5V, you may consider one of these devices with a lower supply voltage and powered-off protection. Keep in mind that in order to take advantage of powered-off protection, VCC must be defined (0V to max VCC) at all times (never floating). 

    Best regards,
    Kate