nrf52 high speed crystal oscillator selection considerations

RE: nrf52 high speed crystal oscillator selection considerations

Najam — Mon, 21 Jun 2021 05:53:45 GMT

Hello again,

These days we could not find the parts which we wanted to use in our original design.

Can we use FA-128 32.0000MF20X-AJ as replacement?
It has the following characteristics
1. Tolerance: ±10 PPM
2. Stability: ±20 PPM
3. Temperature: -20 to 75 Degrees
4. Impedance: 60 Ohms
5. Load Capacitance: 8 pF

I am concerned by the frequency stability parameter.

The Crystal Spec by nordic specifies ±40 PPM tolerance, so we will calculate this like (±20 + ±10) = ±30 PPM for total tolerance?

Thanks in advance.

RE: nrf52 high speed crystal oscillator selection considerations

Najam — Tue, 26 Jan 2021 13:23:33 GMT

Thank you very much for the answer, much appreciated.

RE: nrf52 high speed crystal oscillator selection considerations

ketiljo — Mon, 25 Jan 2021 13:59:52 GMT

The two crystals you refer to should have equal performance. The CL value is important for the current draw and startup time. 8 pF is ok here.

The 300 µW is max drive level the crystal can handle. As long as this number is higher than the drive level of the oscillator, 100 µW, you're good. The XRCGB32M000F1H01R0 part should be a direct replacement.