The TPIC1021 is the LIN (Local Interconnect Network) physical interface, which integrates the serial transceiver with wake up and protection features. The LIN bus is a single wire, bi-directional bus typically used for low-speed in-vehicle networks using baud rates between 2.4 kbps and 20 kbps.

The LIN bus has two logical values: the dominant state (voltage near ground) represents a logic ’0’ and the recessive state (voltage near battery) and represents logic ’1’.

In the recessive state the LIN bus is pulled high by the TPIC1021’s internal pull-up resistor (30k) plus a series diode.

The LIN Protocol output data stream on the TXD pin is converted by the TPIC1021 into the LIN bus signal through a current limited, wave-shaping low-side driver with control as outlined by the LIN Physical Layer Specification Revision 2.