ZHCSJK5C January 2018 – October 2020 TCAN4550-Q1
The WAKE terminal is a high voltage input terminal which can be used for local wake up (LWU) request via a voltage transition. The terminal triggers a LWU event on either a low to high or high to low transition as it has bi-directional input thresholds. This terminal may be used with a switch to VSUP or ground. If the terminal is not used it should be pulled to ground or VSUP to avoid unwanted wake up events.
The LWU circuitry is active in sleep mode and standby mode. If a valid LWU event occurs, the device transitions to standby mode. The LWU circuitry is not active in normal mode. To minimize system level current consumption, the internal bias voltages of the terminal follows the state on the terminal. The wake filter time for a valid wake to avoid glitches on wake pin is provided by filter value of tWAKE(MIN). A constant high level on WAKE has an internal pull up to VSUP and a constant low level on WAKE has an internal pull down to GND. On power up, this may look like a LWU event and could be flagged as such.
RXD_INT is an internal signal and can be seen in Transceiver test mode when VIO is present.