ZHCSJK5C January 2018 – October 2020 TCAN4550-Q1
The TCAN4550-Q1 monitors the VSUP,VIO and VCCOUT pin for undervoltage events. These voltage rails have under voltage detection circuitry which places the device into a protected state if an under voltage fault occurs for UVSUPand UVIO. This protects the bus during an under voltage event on these terminals. If VSUP is in under voltage, the device loses the source needed to keep the internal regulators active. This causes the device to go into a state where communication between the microprocessor and the TCAN4550-Q1 is disabled. The TCAN4550-Q1 is not able to receive information from the bus, and thus does not pass any signals from the bus, including any Bus Wake via BWRR signals to the microprocessor. See Table 8-6.