High-precision clock module based on DS3231SN

I bought a DS3231 clock module from a certain website some time ago. When using it, it resets when the power is off. Finally, I found that the battery holder was soldered (in fact, I later found that the soldering pads of the battery holder were all broken off). I might as well make one myself. . ---------------------------------- Follow-up: I reissued one, but it still has the same problem. As expected, it's not as good as mine. Do. . . (EDA starts!) By the way, I learned about the DS3231 chip and optimized the size of the module. The main function of the memory LR24C32D (C411182) is to store data and cascade other IIC devices. It can actually be omitted. It has been shown in the schematic diagram. To make a distinction, only the basic circuit part can realize the clock function.

After the circuit verification is completed, the Arduino test clock function is correct. The physical size is very small, about 2cm*2cm. The circuit is relatively simple. The main reason is that the battery holder on the back takes up a lot of space. Otherwise, the size can be further reduced. The battery uses a relatively small Small size 1220 button battery