Hello, I'm new to JeeLabs, and I recently purchased a couple of the RTC plugs from the ModernDevice site. I really like the product, but there is one issue with the battery that I think can be improved.
First, here's a little background about my project. I'm working on constructing an acceleration logger using an Arduino, an accelerometer, and a micro-SD card. I wanted to add the RTC to the system so that I could put timestamps on files when they are created. I previously was using the DS1307 on a module from sparkfun.
I was really pleased to find your product because the 3.3V option fits in well with my other components, and it had been working great. Unfortunately, I noticed that the clock would lose its time after some rapid accelerations. After playing around a bit, I think I have narrowed the problem down to the battery being loose and losing contact momentarily, which results in the memory being reset.
The coin cell that came with the JeeLabs RTC is a CR1220. When I replaced this with a CR1225 from the sparkfun RTC, the JeeLabs RTC did not lose memory despite any drops or accelerations. The thickness of the CR1225 seems to fit better with the socket.
I would like to buy several more of these for a research project. I can easily swap out the batteries after I purchase them, but thought I would pass along the suggestion as a possible improvement for the product.
Thanks for the great work!