Can I replace the big crystal oscillator with a smaller oscillator (in size) in MCP2515?

Question

Am using the 'MCP2515 Can Bus Module Board with TJA1050' as a reference in my custom PCB, what I was wondering is that if I can replace the big crystal this board has (look at the image below)

I have already got my PCB manufactured with the same component and everything works as expected and these are it's specifications:

Frequency: 8MHz
Load Capacitor: 20pF
Normal temperature Frequency Tolerance :±20ppm
Operating Temperature: -20℃~+70℃

Now that I want to replace this with a smaller one, can someone please let me know what parameters should I be exactly looking for? I would be the happiest if you give a replacement part number instead :)

Also, can I use a oscillator or resonator, does it matter?

Answer 1

You need to look at the same parameters the existing crystal tells you. Or look at what chip data sheet tells about what kind of crystals it requires or works best with.

If you intend to only replace the existing crystal, you need to know what exact crystal part number you bought - a datasheet is just generic tool for specifcying which part number to buy based on what parameters you want.

1. Frequency (8 MHz) 2a) Series or Parallel resonant mode. 2b) Load capacitance requirement (20pF) indicates parallel mode, not series. It's not the capacitor value.
2. Frequency tolerance. (I guess this is 20ppm).
3. Frequency stability. (Not mentioned).
4. Temperature range.
5. ESR. May or may not be important.
6. Shunt capacitace. May or may not be important.
7. Fundamental or overtone mode ( 8 MHz should be fundamental mode).
8. Cutting angle (AT is very likely).

Dependin on the chip and application, it may be possible to use a ceramic resonator instead of a crystal. But you must know what freqency tolerance you need. You use a 20 ppm crystal. A typical resonator will be 50000 ppm.

Edit: Chip data sheets says you can use crystals or ceramic oscillators. Chip data sheet says for full bus speed range a crystal is required. Maximum allowed node-to-node variation is 1.7%. So you need to decide which speed you want and then decide if that scenario needs a crystal or will resonator do.