TJA1020 Application Note

●Overview

●The TJA1020 is the interface between the LIN master/slave protocol controller and the physical bus in a Local Interconnect Network (LIN). It is primarily intended for in-vehicle sub-networks using baud rates from 2.4 up to 20 Kbaud.

●The transmit data stream of the protocol controller at the TXD input is converted by the LIN transceiver into a bus signal with controlled slew rate and wave shaping to minimize EME. The LIN bus output pin is pulled HIGH via an internal termination resistor. For a master application an external resistor in series with a diode should be connected between pin INH or pin BAT and pin LIN. The receiver detects the data stream at the LIN bus input pin and transfers it via pin RXD to the microcontroller.

●In normal transceiver operation the TJA1020 can be switched in the normal slope mode or the low slope mode. In the low slope mode the TJA1020 lengthens the rise and fall slopes of the LIN bus signal, thus further reducing the already very low emission in normal slope mode.

●In sleep mode the power consumption of the TJA1020 is very low, whereas in failure modes the power consumption is reduced to a minimum.

●MoreLess

●## Features

●General

● Baud rate up to 20 Kbaud

● Very low ElectroMagnetic Emission (EME)

● High ElectroMagnetic Immunity (EMI)

● Low slope mode for an even further reduction of EME

● Passive behaviour in unpowered state

● Input levels compatible with 3.3 and 5 V devices

● Integrated termination resistor for Local Interconnect Network (LIN) slave applications

● Wake-up source recognition (local or remote)

● Supports K-line like functions.

●Low power management

● Very low current consumption in sleep mode with local and remote wake-up.

●Protections

● Transmit data (TXD) dominant time-out function

● Bus terminal and battery pin protected against transients in the automotive environment (ISO7637)

● Bus terminal short-circuit proof to battery and ground

● Thermally protected.

●## Features