CAN FD Shield TLE9371VSJ

Story

In the realm of embedded systems, industrial and automotive applications CAN and its enhanced version, CAN FD, are used for communication between various components such as sensors, actuators and microcontrollers. CAN FD offers significant improvements over standard CAN, such as data transfer speeds of up to 8 Mbit/s and variable payload sizes. Despite these advantages finding cost-effective CAN FD transceiver breakout boards can be challenging, preventing makers from using CAN FD. Since CAN FD transceivers themselves are relatively inexpensive, this article details the design and implementation of an affordable CAN FD breakout board using the Infineon TLE9371VSJ transceiver.

The Infineon TLE9371VSJ Transceiver

The Infineon TLE9371VSJ is a CAN FD transceiver, which is indeed able to achieve transfer speeds of up to 8 Mbit/s.

It guarantees CAN FD protocol operations under all conditions incl. error handling and arbitration scenarios and is fully interoperable with CAN XL protocol.

Featuring a VIO input, the transceiver allows easy and seamless adaptation to the microcontroller’s logic level, making it a versatile component for various projects.

Schematic

Bill of materials:

• U1: CAN FD transceiver TLE9371VSJ, provided by Infineon
• J1: Microcontroller I/F header 6-pin, WR-PHD 61300611121, provided by Würth
• J2: CAN termination (120 Ohm), WR-PHD 61300211121, provided by Würth
• J3: Screw terminal for CAN bus, WR-TBL 691214110002S, provided by Würth
• J4: Jumper VIO=5V, WR-PHD 61300111121, provided by Würth
• J5: Jumper ACTIVE, WR-PHD 61300211121, provided by Würth
• R1: 120 Ohm resistor, WRIS-RSKS 560112116119, provided by Würth
• R2: R3: 60 Ohm resistor, WRIS-RSKS 560112110170, provided by Würth
• C1: 1uF, WCAP-CSGP 885012206026, provided by Würth
• C2: 100nF, WCAP-CSGP 885012206020, provided by Würth
• C3: 470pF, WCAP-CSGP 885012006042, provided by Würth
• C3: 1nF, WCAP-CSGP 885012006044, provided by Würth

VCC supply (J1-5)

A 5V voltage supply is required for the TLE9371VSJ transceiver.

VIO Input (J1-6, J4)

VIO input allows to adapt the logical input and output voltage levels of the transceiver to the microcontroller supply.

If the microcontroller system runs on 5V then jumper J4 (VIO=5V) can be closed to reduce the wiring to the target system.

If the microcontroller system runs on 3.3V then jumper J4 (VIO=5V) must be open and the microcontroller's IO voltage must be connected individually.

STB (J1-1, J5)

The breakout board enables to control the standby pin (STB) of the transceiver.

If the standby feature is not be used within the system then jumper J5 (ACTIVE) can be closed to enable the transceiver operation.

If jumper J5 (ACTIVE) is open then by default the transceiver enters standby mode and must be activated by external connection to STB pin

TxD (J1-2) and RxD (J1-3)

These are the communication pins to the microcontroller's CAN controller.

Termination (J2):

Since Termination is critical for maintaining signal integrity in CAN networks, the breakout board offers a jumper J2 (TERM) to activate standard termination (R1=120 Ohm). For more advanced needs, the board also allows for the installation of components (R2, R3, C3) for split termination. It is important to note that once these components are installed, termination cannot be disabled and standard termination should not be activated simultaneously.

PCB design

A highly flexible breakout board has been designed based on the TLE9371VSJ transceiver. The raw PCB can be ordered from PCB manufacturer Aisler here.

Operation

Keep in mind that the CAN FD Shield TLE9371VSJ just adds the physical transceiver to your microcontroller's integrated CAN controller.

Please refer to the related microcontroller reference manual to get the CAN transceiver connected and CAN controller working in the system.

Summary

The CAN FD Shield TLE9371VSJ allows for the easy addition of a physical transceiver to the microcontroller's integrated CAN controller. It supports CAN FD and CAN XL up to 8 MBit/s.

Special thanks to Aisler for manufacturing the PCBs and to Würth Elektronik for providing the collateral parts.

Very Special thanks to Elias for development, design and documentation of this project.