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I am looking to use this temperature compensated 32kHz crystal oscillator as the heartbeat of a quartz movement wristwatch. I want the superior accuracy and stability over any other oscillators, and the small size compared to ds3231. I would like to run the watch off of a 3.7V lipo cell like this:
https://www.adafruit.com/product/1317

Is it really as simple to use as hooking up Vcc and GND to the battery and the CLK pin will pump out 32kHz? Or do I need other circuitry to get it to work, and do I need some kind of regulation on the battery going into the XTAL?

here is the data sheet:
https://www.sitime.com/products/32-khz-tcxos/sit1566

UPDATE

Per an answer below, I need a regulator Here is my newly proposed circuit:

enter image description here

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The battery has an output voltage of 4.2V when fully charged and the oscillator has an absolute maximum supply voltage of 4.0V, so they should not be connected directly.

You can use a low power voltage regulator (eg. 1.8V). You should follow the datasheet recommendations regarding input and output capacitors, as with any LDO regulator.

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  • \$\begingroup\$ Can you verify the circuit edit I added? \$\endgroup\$
    – Austin Fox
    Commented Mar 15, 2022 at 23:58
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    \$\begingroup\$ Did you notice the part in my answer about following datasheet recommendations on the capacitors? \$\endgroup\$ Commented Mar 16, 2022 at 0:04
  • \$\begingroup\$ I changed the values because the value I put seems to be the most common consensus for decoupling capacitors. I am still learning a lot of these finer details but going forward I will note that detail. With the caps. adjusted to 1 muF, does this circuit look right? \$\endgroup\$
    – Austin Fox
    Commented Mar 16, 2022 at 0:08
  • \$\begingroup\$ The idea is generally okay, however the regulator pin numbers vary with package. Also on the SiT1566 pin 1 is N.C., pin 4 is GND and I'm really not sure what exactly pin 6 would be on a 4-pin package. You may need the 100nF near the SiT1566 if the distance to the regulator and associated output capacitor is too many mm. \$\endgroup\$ Commented Mar 16, 2022 at 0:47
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    \$\begingroup\$ You're welcome. If you do make a PCB in order to be able to use that small part more easily, it's worth double and triple checking pin numbers, dimensions, left-right issues and all that sort of thing. It's very frustrating to get a nice-looking board back from the supplier that requires ugly fixes or is even unusable. \$\endgroup\$ Commented Mar 16, 2022 at 3:30

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