on October 29th 10,488

TJA1050 Transceiver Setup and Configuration Guide

The TJA1050 is a CAN transceiver that connects the CAN protocol controller to the physical bus, providing a reliable, fast, and stable way to transfer data in high-speed networks. This article covers its features, setup, and practical uses, making it easier for you to understand how the TJA1050 enhances data communication.

Catalog

TJA1050 Overview

The TJA1050 acts as a link between the CAN protocol controller and the physical bus, creating a way for data to move smoothly across these points. It’s a reliable solution in high-speed environments, making it suitable for systems where fast, consistent data transfer is required. The design minimizes electromagnetic emissions, which means it helps prevent interference in other parts of the system. This feature is especially valuable in networks where other components are closely packed, and reduced emissions allow these parts to function without disruptions.

When a node is unpowered, the TJA1050 maintains stability, allowing the overall network to stay unaffected. Unlike previous transceivers, this model skips standby mode, making it ideal for partially powered networks where parts of the system may occasionally go into a power-down state without impacting the rest of the network. This capability makes it particularly helpful in automotive or industrial settings where systems often require uninterrupted connectivity.

TJA1050 Pin Configuration

Symbol	Pin	Description
TXD	1	Transmit data input; reads in data from the CAN controller to the bus line drivers
GND	2	Ground
Vcc	3	Supply voltage
RXD	4	Receive data output; reads out data from the bus lines to the CAN controller
Vref	5	Reference voltage output
CANL	6	LOW-level CAN bus line
CANH	7	HIGH-level CAN bus line
S	8	Select input for high-speed mode or silent mode

TJA1050 CAD Design

TJA1050 CAD Symbol

TJA1050 PCB Footprint

TJA1050 3D Model Design

Key Features of TJA1050

High-Speed Data Transmission

The TJA1050 enables rapid data transmission, reaching up to 1 Mbaud, which means it can handle high-speed networks where quick and reliable communication is a priority. This feature is especially useful in settings that require continuous, high-performance data exchange, such as automotive and industrial networks.

Compliance with ISO 11898 Standard

The TJA1050 meets the ISO 11898 standard, ensuring compatibility with other CAN-based systems. This compliance means you can integrate it into various networks without compatibility issues, making it a versatile choice for different projects.

Low Electromagnetic Emission (EME)

With its low electromagnetic emission design, the TJA1050 helps reduce the risk of interference with nearby electronic devices. This feature allows the transceiver to operate effectively, even in environments where devices are closely spaced, like automotive or industrial settings.

Wide Common-Mode Range for Electromagnetic Immunity (EMI)

The TJA1050’s broad common-mode range improves its immunity to electromagnetic interference, helping it maintain stable performance in environments with high electromagnetic noise. This stability is essential for ensuring that data transmission remains unaffected by external disturbances.

Unpowered Node Stability

One of the TJA1050’s unique benefits is its ability to keep the CAN bus stable even when some nodes are unpowered. This feature is valuable in applications where parts of the network may power down occasionally, allowing the rest of the system to function without disruptions.

Transmit Data (TXD) Dominant Time-Out

The TXD dominant time-out function prevents transmission errors by automatically stopping transmission if a dominant state is held for too long. This feature helps protect the network from unintentional interference or signal disruption, supporting overall network stability.

Silent Mode

The silent mode feature lets you disable the transmitter, making the TJA1050 ideal for monitoring or diagnostics. This allows the device to observe network activity without sending any signals, which is helpful in systems where you need to avoid disturbing ongoing data traffic.

Protection Against Automotive Transients

The TJA1050 includes built-in protection against automotive transients, which shields it from sudden voltage spikes. This durability ensures the transceiver can operate reliably in vehicles, where voltage fluctuations are common due to various electrical systems.

Compatibility with 3.3V and 5V Devices

Compatible with both 3.3V and 5V devices, the TJA1050 works well across different systems, giving you flexibility in designing and integrating the transceiver into your projects without voltage compatibility concerns.

Thermal and Short-Circuit Protection

The TJA1050 is equipped with thermal protection and short-circuit resilience, guarding it against overheating and accidental connections to battery or ground. These features improve the device’s durability, making it a reliable choice in applications with high safety and performance demands.

Supports Up to 110 Nodes

With support for up to 110 nodes, the TJA1050 can connect many devices within a network, making it suitable for large systems. This capacity is beneficial in applications where numerous devices need to communicate effectively without overloading the network.

TJA1050 Functional Block Diagram

The TJA1050’s block diagram visually represents the way this component manages data flow. It illustrates how the transceiver sends and receives data signals, maintaining a balanced output between the CANH (high-level) and CANL (low-level) lines. This balance is key to controlling electromagnetic interference, enabling the device to handle high data rates with ease. Each section of the block diagram shows how data is processed and transmitted, which helps you understand the device’s overall operation.

It’s designed with flexibility, handling speeds up to 1 Mbaud while staying compliant with CAN standards, including ISO 11898. This approach allows the TJA1050 to adapt to various applications seamlessly, showing the device’s functionality and stability in high-speed data communication environments.

TJA1050 Circuit and Applications

TJA1050 Automotive Transient Test Circuit

TJA1050 Specifications

Technical specifications, attributes, parameters, and comparable parts for NXP USA Inc. TJA1050T/N,118.

Type	Parameter
Mounting Type	Surface Mount
Package / Case	8-SOIC (0.154, 3.90mm Width)
Surface Mount	YES
Operating Temperature	-40°C ~ 150°C
Packaging	Tape & Reel (TR)
Published	2002
JESD-609 Code	e0
Part Status	Obsolete
Moisture Sensitivity Level (MSL)	1 (Unlimited)
Number of Terminations	8
Type	Transceiver
HTS Code	8542.39.00.01
Voltage - Supply	4.75V ~ 5.25V
Terminal Position	DUAL
Terminal Form	GULL WING
Peak Reflow Temperature (Cel)	NOT SPECIFIED
Number of Functions	1
Supply Voltage	5V
Terminal Pitch	1.27mm
Time@Peak Reflow Temperature-Max (s)	NOT SPECIFIED
Base Part Number	TJA1050
Pin Count	8
JESD-30 Code	R-PDSO-G8
Qualification Status	Not Qualified
Power Supplies	5V
Supply Current-Max	0.075mA
Data Rate	1000 Mbps
Protocol	CANbus
Number of Drivers/Receivers	1/1
Duplex	Half
Receiver Hysteresis	70mV
Number of Transceivers	1
Length	4.9mm
Height Seated (Max)	1.75mm
Width	3.9mm
RoHS Status	ROHS3 Compliant

Frequently Asked Questions [FAQ]

1. What is the difference between TJA1050 and MCP2551?

The TJA1050 and MCP2551 both act as interfaces between the CAN protocol controller and the physical CAN bus, but they have unique features. The TJA1050 is designed for high-speed CAN networks, supporting differential transmission and reception between the controller and bus. It’s suitable for networks where nodes may be powered down without affecting the rest of the system. The MCP2551, on the other hand, also supports high-speed CAN but is known for its fault tolerance, protecting the controller from high-voltage spikes caused by external sources like EMI and ESD. This feature provides an extra layer of stability on the bus, especially in environments prone to electrical noise.

2. What are the typical CAN voltage levels?

CAN bus voltage levels vary depending on the line. On the CANH (high) line, the voltage usually sits between 2.5 and 3.5 volts when idle, typically around 2.7 to 3.3 volts during operation. On the CANL (low) line, the voltage generally ranges from 1.5 to 2.5 volts when idle and between 1.7 to 2.3 volts in running conditions. These levels help maintain a clear differential signal, which is necessary for reliable data transmission on the CAN bus.

3. Under what conditions does the TJA1050 operate?

The TJA1050 operates within a supply voltage range of 4.75V to 5.25V. It’s a compact module, measuring 22.0 mm in length, 11.5 mm in width, and 3.3 mm in height, with a weight of about 0.8 to 1.0 grams. The TJA1050 can support up to 110 nodes, making it suitable for larger CAN networks where multiple devices need to communicate seamlessly.

4. Can a Raspberry Pi communicate with a CAN bus?

Raspberry Pi doesn’t come with a built-in CAN bus interface, but it does include an SPI bus on its GPIO pins, which is widely supported by many CAN controllers. The SPI bus uses four connections: MOSI (Master Out Slave In), MISO (Master In Slave Out), SCLK (Serial Clock), and CS (Chip Select), allowing the Raspberry Pi to interface with a CAN transceiver module for CAN communication.

5. How does the MCP2515 CAN bus controller interface with the TJA1050 driver and SPI interface?

The MCP2515 CAN module, combined with the TJA1050 transceiver, enables CAN communication through an SPI interface. This module meets CAN V2.0B standards and supports data rates of up to 1 Mbps. It operates on a 5V DC power supply and has an 8MHz crystal oscillator with a 120Ω termination resistor for signal stability. By connecting to an SPI interface on microcontrollers like Arduino, this module allows seamless control over CAN bus devices, enabling applications in long-distance data transmission and signal radiation prevention.