18.1.3 Bus Pin (LIN_BUS)

A low-side driver with internal current limitation and thermal shutdown, as well as an internal pull-up resistor according to LIN Specification 2.x, is implemented. The voltage range is from -27V to +40V. This pin exhibits no reverse current from the LIN bus to V_S, even in the event of a LIN_VSS shift or V_BAT disconnection. The LIN receiver thresholds comply with the LIN protocol specification.

The fall time (from recessive to dominant) and the rise time (from dominant to recessive) are slope controlled.

During a short circuit at LIN_BUS to V_BAT, the output limits the output current to IBUS_LIM. Due to the power dissipation, the chip temperature exceeds Toff and the LIN_BUS output is switched off. The chip cools down and after a hysteresis of T_HYS, switches the output on again. LIN_RXD stays on high because LIN_BUS is high.

During a short circuit from LIN_BUS to LIN_V_SS, the IC can be switched into Sleep mode, and even in this case, the current consumption is lower than 100 µA. If the short circuit disappears, the IC starts with a remote wake-up.

The reverse current is <2 µA at pin LIN_BUS during loss of V_BAT. This is optimal behavior for bus systems where some Responder nodes are supplied from battery or ignition.