• The real-time clock counts minutes, seconds, date, hours, month day of the week, year and leap-year compensation upto 2100.
• 318 temporary data storage RAM
• Working current of 2.0V, less than 300nA
• Read / Write clock or RAM data with two kinds of mode of single-byte transfer mode and multi-byte character set
• 8 pin DIP package or optional 8 pin SOIC package based on the surface assembly
• Simple 3 wire interface
• Compatible with TTL Vcc=5V
• Double power supply pipe for main power and backup power supply.

DS1307 RTC REAL TIME CLOCK MODULE which adopts the I2C protocol to communicate with SCM, and there was this kind of interface on Arduino, therefore is very convenient to link with each other. DS1307 has a programmable waveforms output, it can be used to drive LED lights, or trigger a certain event as a break-off, but be careful when you use it to take some kind of high-power module. We design the real clock module to pin out the I2C interface of Ds1307 and programmable waveforms output interface SQW are connected, but usually, we will only use the I2C interface to realize the basic set of the clock/read function. Note, that this module must be installed on the battery and can work normally. The battery is button batteries (type CR2032 will be better), the positive upward:

• Size: 38mm (length) * 22mm (W) * 14mm (height)
• Operating voltage: 3.3 – 5 .5 V
• DS3231M at the core
• Clock Accuracy: 5ppm 0-40 C
• Two programmable alarms
• Programmable square-wave output
• DS3231M Datasheet
• LIR2032 / CR2032 backup battery holder for uninterrupted time management (battery not included)
• Wiring instructions (with Arduino Uno R3 for example):
• SCL A5
• SDA A4
• VCC 5V
• GND GND

• Dimensions: 40 x 27 x 15 (LxWxH) mm
• Weight: 10gm (without Hat).
• 2.54mm pin interface leads
• Operating Voltage: 5V.
• Long service life and stable performance
• Standard interface and electronic building blocks
• Widely use in Arduino DIY projects
• Cross rocker as a two-way 10K resistor, with the rocker in a different direction