ISO6720-Q1: Undetermined Output State

Go Bravos

Part Number: ISO6720-Q1

Hi team,

Many digital isolator data sheets have a similar function table in them like this:

My question is regarding the condition where the output side is unpowered, it says the output is “undetermined”.

Does that mean the device could output some arbitrary voltage? Or if I use a pull-down resistor, will that ensure the output remains low under this condition?

over 2 years ago

+1 Andrew J over 2 years ago

TI__Mastermind 23215 points

Hello Go,

Thank you for your question. Your understanding is correct. When Vcco is PD the device is in an undetermined state. In this state the device's output voltage is undeterminable. As you have suggested, using a pull-down resistor would ensure the output is low in this state.

Here is a similar post that can explain in more detail if needed. (23) ISO7760: Need clarification for "undetermined" output state - Isolation forum - Isolation - TI E2E support forums

Let me know if you have more questions.

Best,

Andrew