MCP2518FD breakout boards not responding on SPI bus

TECHNICAL SUPPORT Communication Modules
1

Customer:

I’ve spent weeks trying to get these MCP2518FD breakout boards to work without success. I tried:

– Two different Linux kernel versions (6.6 and 6.12 series) with kernel debugging
– Custom test driver
– Low-level SPI with BusPirate 3.6
– Oscilloscope and logic analyzer examination
– Micro-controller firmware (RP2040) from GitHub - kentindell/canis-can-sdk: Canis Labs CAN SDK · GitHub
– Desoldered one MCP2518FD from a board and verified the board itself is OK

None of these approaches worked. The board never responds on the SPI bus.

I decapped the controller I desoldered and found something suspicious: approximately 80% of the die appears to be occupied by a ROM. Have you received other customer reports about problems with this board? How do you test the boards you sell? I can provide photos of the die and packaging.

Originally submitted via email support on 29 August 2025. Migrated to the forum for community visibility.

2

Customer:

Photo of the decapped MCP2518FD die showing what appears to be a mask ROM occupying most of the die area.

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3

Customer:

Barcode from the board packaging.

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4

Soldered Support:

We’ve tested this exact breakout from our warehouse and confirmed receiving and transmitting work correctly.

Several things to check:

  1. The JP1 jumper must be soldered to connect the termination resistors on the endpoint transceiver nodes. This should be added to the documentation.

  2. Test using our library with a MCU: GitHub - SolderedElectronics/Soldered-CAN-Bus-Breakout-MCP2518-Arduino-Library: CAN Bus Breakout with MCP2518 Soldered Arduino Library · GitHub

  3. Some boards may need a 470uF capacitor added between the VCC and GND pins of the transceiver to stabilize the input, though the probability of all 6 units having this issue is very low.

  4. Refer to the documentation for hookup details: CAN Transciever MCP2518 - Getting started and Initialization | Soldered Documentation

We haven’t had these kinds of complaints with this breakout before. A tester device for validation is currently in development. We can send tested units for comparison if needed.

Attachment omitted in migration: MCP2518.mp4