DS1307

64 x 8, serial, I2C real-time clock


X1	1 •	8	Vcc
X2	2	7	SQW/OUT
V_BAT	3	6	SCL
GND	4	5	SDA

Pin	Symbol	Description
1	X1	32.768kHz crystal connection
2	X2	32.768kHz crystal connection
3	V_BAT	backup supply voltage (e.g. 3V lithium coin cell)
4	GND	ground
5	SDA	serial data input/output
6	SCL	serial clock input
7	SQW/OUT	square wave output
8	Vcc	primary supply voltage

Notes

A lithium battery with 48 mAh or greater will back up the DS1307 for more than 10 years.
Square wave output can be 1Hz, 4.096kHz, 8.192kHz, or 32.768kHz.
Reads/writes are inhibited when Vcc falls below 1.25 x V_BAT.

Note: Data is maintained by an independent source and accuracy is not guaranteed. Check with the manufacturer's datasheet for up-to-date information.