DS1307 Serial Real-Time Clock IC DIP-8

DS1307 Serial Real-Time Clock IC DIP-8 is a low-power, full binary-coded decimal (BCD) clock/calendar device designed to provide highly accurate timekeeping for microcontroller-based systems. This integrated circuit manages seconds, minutes, hours, day, date, month, and year information, automatically adjusting for months with fewer than 31 days and including leap year compensations valid up to the year 2100. Furthermore, the DS1307 operates as a slave device on the I²C bus, which allows for simple interfacing with just two wires. The device also features a built-in power-sense circuit that detects power failures and automatically switches to the backup battery supply. Consequently, your system maintains precise time even during a complete loss of primary power. Therefore, developers widely choose this IC for data logging, clocks, and various time-sensitive embedded applications.

Key Features:

• Complete Timekeeping: The IC tracks all time units from seconds to years with leap year compensation, ensuring long-term schedule accuracy.
• I²C Serial Interface: It utilizes a simple two-wire interface (SDA and SCL) to communicate with the host processor, saving valuable GPIO pins.
• Nonvolatile Storage: Includes 56 bytes of battery-backed, general-purpose RAM for storing user-specific data or system configuration settings.
• Automatic Battery Backup: The internal circuitry monitors V_CC and seamlessly switches to a backup battery source to prevent data loss during power outages.
• Programmable Square-Wave Output: Provides a dedicated pin capable of generating one of four square-wave frequencies: 1Hz, 4.096kHz, 8.192kHz, or 32.768kHz.

Technical Specifications:

• Operating Voltage (V_CC): 4.5 V to 5.5 V
• Battery Backup Voltage: 2.0 V to 3.5 V (Typically 3.0 V)
• Supply Current (Active): ≈ 1.5 mA
• Supply Current (Timekeeping Mode): < 500 nA
• Interface Frequency: 100 kHz (I²C Standard Mode)
• Operating Temperature: −40°C to +85°C
• Clock Format: 12-hour (with AM/PM indicator) or 24-hour format

Mechanical Specifications:

• Package Type: DIP-8 (Dual In-line Package)
• Mounting Type: Through-Hole Technology (THT)
• Lead Finish: Matte Tin
• Package Material: Molded Plastic (Epoxy)

Dimensions:

• Body Length: ≈ 9.27 mm
• Body Width: ≈ 6.35 mm
• Total Height (including pins): ≈ 4.57 mm
• Pin Pitch: 2.54 mm (0.1 inch)
• Row Spacing: 7.62 mm (0.3 inch)

Pinout and Wiring:

• Pin 1, 2 (X1, X2): Connections for a standard 32.768 kHz quartz crystal.
• Pin 3 (V_BAT): Backup battery input (typically connected to a 3V CR2032 lithium cell).
• Pin 4 (GND): System ground connection.
• Pin 5 (SDA): Serial Data Input/Output for the I²C bus; requires a pull-up resistor.
• Pin 6 (SCL): Serial Clock Input for the I²C bus; requires a pull-up resistor.
• Pin 7 (SQW/OUT): Square-Wave/Output Driver pin.
• Pin 8 (V_CC): Primary DC power supply input.

Datasheet Reference:

• Download DS1307 Datasheet

Commonly Used in:

• Arduino Projects: Used extensively in DIY digital clocks and scheduling systems.
• Data Loggers: Provides time-stamping for environmental sensors or industrial monitoring equipment.
• Home Appliances: Found in ovens, washing machines, and thermostats that require time-of-day functions.

Applications:

• Real-Time Scheduling: Activating or deactivating industrial machinery at specific times of the day.
• Attendance Systems: Recording exact check-in and check-out times for security and payroll.
• Point of Sale (POS) Terminals: Managing transaction timestamps even after system reboots.

Equivalent Models:

• DS1302: A similar RTC from the same family, however, it uses a 3-wire synchronous interface instead of I²C.
• PCF8563: A popular CMOS real-time clock and calendar optimized for low power consumption.
• DS3231: A higher precision RTC with an integrated temperature-compensated crystal oscillator.

Package Includes:

• 1 x DS1307 Serial Real-Time Clock IC DIP-8