G+_David McNamara Posted January 30, 2017 Share Posted January 30, 2017 Hi Padre and Bryan. I really enjoy the shows and the amount of effort and enthusiasm you put into them. In episode 281 you showed a number of different sensors, one of which was the TinyRTC. I have a few words of caution about that particular component. On bangood.com you will see a number of different listings for the DS1307-based RTC where it is available in different quantities. In some of the listings they mention (and even have photos in some of them) that the battery used is an LIR2032 and others it's listed as a CR2032 battery. The TinyRTC is actually designed for use with the LIR2032, lithium ion rechargeable battery, NOT the CR2032. The circuit actually has a charging circuit built in which, when used with a CR2032, could end up causing serious problems (think exploding batteries or even fire) if you use a CR2032 non-rechargeable battery. The first time I purchased one of these modules, I picked it up from a local electronics store here in New Zealand. It was in a blister pack and actually came with a CR2032 already installed in the blister pack! What alerted me to the problem was the back of the packed mentioned it included an LIR2032 battery. So be very careful! The other thing to be aware of is that (as far as I am aware) the charging circuit is constantly charging - it does not stop if the LIR2032 is fully charged. This has the effect that if you are running your project off a battery, it is constantly drawing power and so your battery will last no where near as long as you might expect it to. So one way around both these issues is to modify the circuit to disable the recharging circuit and just use a CR2032 (which will last for at least 12 months anyway). Here is a link to where one guy has documented how to go about modifying the TinyRTC: http://ik1zyw.blogspot.co.nz/2015/04/modding-rtc-ds1307-for-non-rechargable.html Good luck with your builds. David. http://ik1zyw.blogspot.co.nz/2015/04/modding-rtc-ds1307-for-non-rechargable.html Link to comment Share on other sites More sharing options...
Recommended Posts