Home made ds3231 circuit failed

guys, I think it is the wires i used are not good, so made the scl unstable.... After using some new wires, the module works as expected. It is strange that the tmp117 seems to be more tolerant to poor wires.

Having single header pins distributed across the board just isn't a good idea in my experience. They tend to wiggle and exhibit poor contacts more so than if you put e.g. 4 of them in a row.

Where's the battery? There's none shown in the photo.

According to the datasheet if the battery is not used then VBAT should be connected to GND. This tidbit is buried in the 'PIN DESCRIPTION' for pin 14.

Don

thanks.

okay. i will keep that in mind