NXP公司的TJA1021是LIN 2.0/SAE J2602收發(fā)器。它在本地互聯(lián)網(wǎng)絡(luò)(LIN)主/從協(xié)議控制器和LIN中物理總線間進行接口。它和LIN 2.0/SAE J2602標準兼容，在車內(nèi)的子網(wǎng)絡(luò)的波特速率從1 kBd 到 20 kBd。它和TJA1020引腳兼容，并改進了ESD保護性能。本文介紹了TJA1021的主要性能，方框圖以及和微控制器間的典型應(yīng)用電路圖。

LIN 2.0/SAE-J2602 standalone transceiver TJA1021

LIN lets you easily interconnect locally applied sensors, actuators and switches (in switch panels, door and seat modules for example) to the CAN backbone with a standardized front end. This helps significantly reduce costs and design-in effort for a wide range of human reaction time triggered applications, such as powered mirrors and windows.

The rapid adoption by automotive makers of the LIN 2.0 protocol has made this cost-effective,low-speed serial communication system bus the natural choice for arbitration-free local communications. Optimized for reliable and cost-effective LIN master and slave node implementations, with its sleep current consumption < 10μA and providing IEC-61000-4-2 compliant ± 6 kV ESD protection, the TJA1021 gives you the leading-edge when creating LIN systems.

The TJA1021 is the interface between the Local Interconnect Network (LIN) master/slave protocol controller and the physical bus in a LIN. It is primarily intended for in-vehicle sub-networks using baud rates from 1 kBd up to 20 kBd and is LIN 2.0/SAE J2602 compliant. The TJA1021 is pin-to-pin compatible with the TJA1020 and improved on ElectroStatic Discharge (ESD).

The transmit data stream of the protocol controller at the transmit data input (TXD) is

converted by the TJA1021 into a bus signal with optimized slew rate and wave shaping to minimize ElectroMagnetic Emission (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 VBAT 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 sleep mode the power consumption of the TJA1021 is very low. In failure modes the

power consumption is reduced to a minimum.

主要特性：

通用特性

LIN 2.0/SAE J2602 compliant

Baud rate up to 20 kBd

Very low ElectroMagnetic Emission (EME)

High ElectroMagnetic Immunity (EMI)

Passive behavior in unpowered state

Input levels compatible with 3.3 V and 5 V devices

Integrated termination resistor for LIN slave applications

Wake-up source recognition (local or remote)

Supports K-line like functions

Pin-to-pin compatible with TJA1020

低功耗管理

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

保護性能

High ESD robustness: ?6 kV according to IEC 61000-4-2 for pins LIN, VBAT and

WAKE_N

Transmit data (TXD) dominant time-out function

Bus terminal and battery pin protected against transients in the automotive

environment (ISO 7637)

Bus terminal short-circuit proof to battery and ground

Thermally protected

主要優(yōu)勢:

Helps meet car maker’s ESD requirements without the need for external components

Low quiescent current (< 10μA) helps meet more relaxed current consumption targets

Leadless HVSON8 package offers 60% board space reduction compared to SO8

Fail-safe features allowing easier design-in

Easily interfaces with a wide range of microcontrollers

Zero reverse bus current allows partial networking without introducing extra network design complexity

Drop-in replacement for TJA1020