Real Time Clock DS1307 RTC I2C Module AT24C32 with CR2032 Coin Battery

DS1307 RTC Module Introduction

The DS1307 RTC module keeps track of the current date and time. It is used in electronics projects for time keeping, data logging, building clocks, timers etc. This module runs on the DS1307 RTC chip and also contains the 24C32 EEPRROM for accurate time keeping in terms of seconds, minutes, hours, days, and months. Moreover, time in both 12 hour and 24 hour format can be accessed through this module. It has a very accurate real time clock which houses a 32 kHz crystal oscillator.

On the backside, it possesses a 20mm 3V lithium coin cell holder which fits a CR2032 battery. This battery is extremely vital in tracking the time and making sure it stays correct in case the main power is cut off. Therefore, the CR2032 cell acts as a backup battery source incase the main power is lost.

DS1307 RTC Module Pinout

The diagram below shows the pinout of the DS1307 RTC module.

As you can see in the diagram above, the DS1307 module consists of a total of twelve pins but we only require pins 2 to 5 to access the current time using a single module. These include the I2C communication pins (SCL and SDA) and the power supply pins (VCC and GND).

Specifications

Let us look at some key specifications of the DS1307 RTC module.

• Operating voltage of 4.5 – 5.5V
• Current consumption is less than 1.5mA
• 3V CR2032 Coin Cell as battery source
• Square wave output signal which is programmable
• Detects power failure automatically and switches circuitry accordingly