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For the latest iteration of my prototype, I replaced a quartz oscillator with (what I thought would be) a drop-in MEMS replacement: the DSC6013CI2A-033.0000. It is suppling a 33 MHz clock to a TLC5955 led driver, trough a 51 ohm resistor (starting from pin 3 on the MEMS):

enter image description here

The previous hand-assembled iteration with the XO worked fine, but this one (assembled by a third party) doesn't seem to be running. 3v3 is present at the decoupling cap below the MEMS. Apart from the MEMS not being soldered correctly and not making contact, could it be that somehow the trace capacitance is too much for the MEMS? And the MEMS output driver is just blown? The datasheet states that this is the "low-drive" version, which has a 1mA drive capacity along with a 15pf load capacity (stated on the mouser product page).

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  • \$\begingroup\$ This operates at 66MHz /2 so any faults are logical not short fat tracks. Check for shorts? \$\endgroup\$ Commented Sep 23, 2019 at 22:21

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If your not getting and output from the MEM's Oscillator then the first thing to do is find out if its the design or the oscillator. Usually when these things happen I do the soldering work myself and make sure no soldering temperatures exceeded temperatures in the datasheet.

The oscillators themselves are pretty simple and you should be seeing some kind of output since yours is the type that has a buffer. Make sure you have the DSC6013 and make sure the layout matches below. (you don't have a bypass cap near the oscillator, so if your Vcc is noisy this could be a problem).

enter image description here
Source: https://nl.mouser.com/datasheet/2/268/20005625B-1149229.pdf

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  • \$\begingroup\$ Altough not entirely laid out as in the recommended board layout, there is a bypass cap just below the MEMS. It's a bit to see because its outline is hidden in the picture, but it has "1" and "2 GND" labeled. I'd have to break out the microscope to verify if they'd actually put a DSC6013 on there.. \$\endgroup\$ Commented Sep 24, 2019 at 23:08
  • \$\begingroup\$ For a clock the proximity of the bypass cap makes a difference \$\endgroup\$
    – Voltage Spike
    Commented Sep 25, 2019 at 4:03
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It turned out the decoupling cap I used was too small: 10n instead of 100.

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