THVD2450: Power applied to input of an unpowered device

David DiPaola

Part Number: THVD2450

Tool/software:

What happens if a signal is applied to inputs A and /or B without power is applied to Vcc?

What does the input protection circuitry look like? An equivalent diagram is okay. I am trying to perform a sneak circuit analysis. Thank you.

over 1 year ago

+1 Clemens Ladisch over 1 year ago

Guru 317480 points

The absolute maximum ratings allow this. There is still some leakage current (see the I_I specification).

The protection circuitry uses (the equivalent of) Zener diodes to clamp larger voltages.

0 Danny Bacic over 1 year ago

TI__Mastermind 26826 points

David,

Clemens is correct. The devices are capable of withstanding these conditions in unpowered state, and the worst-case leakages are provided as "input current" characteristics in the Electrical Characteristics table.

Best,

Danny

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THVD2450: Power applied to input of an unpowered device