Replacing capacitors (load capacitance) for external crystal

Thread Starter

Xavier Pacheco Paulino

Joined Oct 21, 2015

I have a very old board where the microcontroller stage doesn't turn on. The power supply circuitry is okay. I then realized that one of the capacitors next to microcontroller crystal (4 MHz), like shown below, is kind of cracked up because of age. The marking code says 22J, so I guess they are 22pF. I don't have that value available right now, I just have 2200pF, 0.01uF and 0.047uF. I guess I will have to replace both of the capacitors to make them match. So, how do I determine if I strictly need the same capacitor value, or other values work?

Last edited: