Crystal Oscillator Resistance To Impact Damage - Page 1
Forum section: electronics / general

author: jonovid
author_rank: Super Contributor
timestamp: May 16, 2022, 12:58:33 am
content: I have had a number of electronics appliance's that have failed from impact damage.It slid off the table, a family member or pet knocked it over.a drop on the floor. all electronic appliance's had a microcontroller with a crystal oscillator.all had no visible signs impact damage. only that the microcontroller had failed. the pcb was dead.so how robust is a quartz crystal to impact damage?is removing crystal from a pcb for testing worthwhile for the effort spent?it see if the crystal is off or on its labeled frequency.for most video equipment crystal oscillator frequency is of critical importance.so a bad crystal or off frequency crystal oscillator is a failed microcontroller .if this is true? I can save. at lest two non working electronics appliances just by replacing a crystal or crystal resonator.any suggestions.

author: ataradov
author_rank: Super Contributor
timestamp: May 16, 2022, 01:09:48 am
content: It is virtually impossible to damage the crystal by falling from a table. It takes quite a bit of effort to actually damage them. And in case of a fall damage, appliance enclosure would absorb most of the impact energy.Cracked joints, dislodged connectors and stuff like this is more likely.

author: RoGeorge
author_rank: Super Contributor
timestamp: May 16, 2022, 09:16:12 am
content: Quote from: jonovid on May 16, 2022, 12:58:33 amI've once had a toy drone that felt from about 10 meters height. It never start again, didn't try to repair and gave the drone to a friend, to repair it for his kid. He told me the quartz was broken.Never ever happened to me to encounter a broken quartz, except then.The most often defects I found in occasional repairs of recent appliances are bad electrolytic capacitor (dried/bulged/high ESR), internally shorted MLCC capacitors, or failure of high power components.

author: Dr. Frank
author_rank: Super Contributor
timestamp: May 16, 2022, 10:52:46 am
content: Whether an XTAL fails on vibration or drop, depends on its inner construction, i.e. the suspension of the blank.In Automotive application, we had different classes of XTALs, or package types, depending on the application, either Interior, or Powertrain.Such failures could also be related to the connection of the component (also of other components), like SMD versus through-hole, or different realization of SMD connection techniques.In the end, yes it makes sense to check the XTAL in such cases. I would expect a complete failure instead of a frequency shift, anyhow.Frank

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: May 16, 2022, 11:13:25 am
content: I have had some xtals that I replaced and the radio worked. I think one of the xtals actually looked OK on a Spectrum Analyzer, but did not work in the radio. Another xtal worked.However, I would think it is more likely something else is broken, probably something very hard to see. A solder joint or such.These little xtals are usually very tough.If you happen to have a spare xtal, there is nothing to loose by trying it.Wally

author: Benta
author_rank: Super Contributor
timestamp: May 16, 2022, 07:06:21 pm
content: The most usual type of crystal is the AT-cut (MHz range), which is quite rugged. I've never seen one break from impact on dropping the device.Another story is the small tubular 32 kHz types, that are "tuning fork" cut. They are somewhat sensitive, especially if they are not mounted correctly.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: May 18, 2022, 12:49:19 pm
content: I was just working on a radio yesterday and leaving it to just Rx, on USB, it went silent.The 7.8025 USB/AM Xtal bit the dust.No reason except it is old

author: Gyro
author_rank: Super Contributor
timestamp: May 18, 2022, 09:05:30 pm
content: I remember production line reliability problems with HC18 packaged crystals stored in bins. That clinking sound masks some very high G forces. The higher the pitch, the higher the deceleration.Edit: That was direct metal package to package contact though. Accelerations drop off very rapidly as soon as you have anything remotely compliant (like a PCB) involved.

author: JPortici
author_rank: Super Contributor
timestamp: May 19, 2022, 05:35:42 am
content: Quote from: ataradov on May 16, 2022, 01:09:48 ammy car key fell from the counter and refused to work. Granted, i tought about a cracked joint but in the end it was the crystal who had cracked open. Key works like a charm after replacing the crystal.Also my boss doesn't like it when i put oscillators in a board and i should use the internal oscillator whenever possible (accuracy is usually fine so no problem there). Apparently in the past there were numerous cases of board falling from a table during some manufacturing operation (final assembly/potting/testing) and they would not work because the crystal failed