• Resolved

ISO7741-Q1: I/O Signal Voltage feedback to VCC1/VCC2?

Part Number: ISO7741-Q1

Good morning team,

I am working on an application with ISO7741-Q1 and ISO7721-Q1. In this system, during sleep mode, the supplies will be turned off and some of the input/output digital isolator pins will be pulled to +5V. In this case, is there a possibility of the input/output signal voltages feeding back to VCC1/VCC2 through the device's internal circuitry?


Brian Angiel

  • Hi Brian,

    Thank you for sharing details regarding your query.

    As mentioned in datasheet section 8.4.1, all I/O pins have protection diodes that bypass higher input voltage (INx > [VCC+0.5V]) to its supply. Hence device can potential power up from device I/O pin if the voltage exceeds supply voltage.

    These protection diodes are designed to protect against ESD and are not meant for continuous voltage operation. Hence I do not recommend operating device in such conditions.


    Koteshwar Rao