5.10.3 LIN Transceiver Behavior under Low Supply Voltage Condition

After supplying power to the device, the voltage at the VS pin increases according to the connected blocking capacitor. If V_VS is higher than the minimum VS operating threshold V_{VS_PWRON}, the LIN Transceiver mode changes from LIN Unpowered mode to LIN Standby mode. As soon as V_VS exceeds the undervoltage threshold V_{VS_UV_Clear}, the LIN transceiver can be activated when the device is in Normal mode.

If, during LIN Standby mode, the supply voltage on the VS pin drops below the VS operating threshold V_{VS_PWROFF}, then the LIN transceiver switches to LIN Unpowered mode.

If, during LIN Normal mode, the voltage level on the VS pin drops below the VS undervoltage detection threshold V_{VS_UV_Set}, the LIN transceiver switches to LIN Standby mode. As a result, the LIN transceiver is disabled in order to avoid malfunctions and false bus messages. If the VDD1 or VDD2 voltage drops below the corresponding undervoltage threshold, V_{VDD1_UV_Set}, V_{VDD1_IO_UV_Set}, V_{VDD2_IO_UV_Set}, the LIN transceiver will also switch to LIN Standby mode, as the device will transition to MCU Reset mode. LIN bus wake-up is not possible while a VS undervoltage is detected.