SLVSHF5 November 2024 TLC6989
PRODUCTION DATA
The TLC6989 monitors the SPI for communication with an internal watchdog timer. The device expects to receive a valid SPI command within the communications loss interval. The timer starts counting when the device enters the Normal state. The timer resets when a valid SPI command is detected. When the watchdog timer overflows, device automatically switches to Failsafe state and sets the DEV_STATE to 0x3 and FLAG_ERR is set to 1. The SPI controller can access the TLC6989 and write 1 to EXIT_FS in register DEVCTRL to set the device to Normal state again when the communication recovers. The watchdog timer is programmable by 2-bit field SPI_WDT_CFG in register SPICTRL. Disabling the watchdog timer by setting SPI_WDT_CFG to 0x3 prevents the device from automatically entering into Failsafe state.