DRV8706-Q1: Inquiry Regarding Loopback Test Strategy for DRV8706-Q1 in Safety-Critical Application

Tool/software:

We are using the DRV8706-Q1 in a safety-critical automotive ECU and are implementing a mechanism to detect slave device disconnection or SPI communication faults.

Our strategy involves periodically writing a known pattern (like 0x55 or 0xAA) to a general-purpose read/write register and reading it back immediately. A mismatch would indicate a fault. This check is scheduled in software every 100ms.

We have identified the IC_CTRL register (address 0x04) as a possible candidate. To avoid affecting driver operation, we mask critical bits during write and restore the original value after the check.

We would like to know:

1. Is there any provision in the device to support this kind of loopback test, such as a scratchpad register?
2. Do you have any suggestions or concerns regarding using IC_CTRL with masked writes and restoration for this purpose?

Your feedback will help us ensure safe and reliable implementation.