I have an attiny2313 conntected to a DS1307 and a 32.768kHz crystal. The problem is that the ds1307 get's hot.
- I tripple checked the connections
- I swapped out the IC by 2 others, no succes.
Than I swapped out the crystal by 2 others, and with number 3 the DS1307 stopped getting hot.
I tried the previous DS1307 they also didnt get hot. So the problem apparently lies in the crystals.
The problem I'm having now is that the DS1307 does not count. I can wright and read data via the I2C bus but the seconds and minutes do not change.
Looking up the problem on the internet, I found me to this webpage
http://www.sciencetronics.com/greenphotons/?p=798
I know that the webshop where I buy them does not sell stuff of 'legit' brands. So 9/10 chance I have chinese clones in me hands.
The strange part is that I have a working ds1307 in an other project, bought of the same webshop with the same crystals.
Does anybody have seen this problem before? I have tried 3 different chips and 3 different crystals and it still does not work.
I now contacted the webshop and asked for the specific load capacitance. They say it is 20pF. Datasheet of DS1307 says: "The internal oscillator circuitry is designed for operation with a crystal having a specified load capacitance (CL) of 12.5pF"
Can this too high load capacitance actually lead to the frying temperatures?