DS3231 RTC Module Precise Real Time Clock I2C AT24C32

DS3231 RTC Module Precise Real Time Clock I2C AT24C32 is a highly accurate, low-cost I2C real-time clock (RTC) that maintains exceptionally precise timekeeping even in fluctuating environments. This module integrates a temperature-compensated crystal oscillator (TCXO) and a crystal to ensure long-term stability, addressing the common drift issues found in basic RTC chips. Furthermore, the board includes an AT24C32 EEPROM chip, providing 32K bits of non-volatile storage for user data or system logs. Consequently, you can maintain the time and date with seconds, minutes, hours, day, date, month, and year information reliably. The module also features a battery backup input, which allows the device to keep time even when the primary system power is disconnected. Therefore, this module represents an ideal solution for data logging, clocks, and any project requiring time-stamping with high precision.

Key Features:

• High Precision Timekeeping: The internal TCXO maintains accuracy within ±2ppm, which equates to less than two minutes of deviation per year.
• Integrated Temperature Sensor: An on-chip sensor monitors temperature and automatically adjusts the oscillation frequency to compensate for thermal changes.
• Onboard EEPROM: Features the AT24C32 storage chip, allowing you to save up to 4KB of configuration data or log entries via the I2C bus.
• Battery Backup Support: Includes a battery holder for a CR2032 or LIR2032 cell, ensuring the clock continues to run during power outages.
• Programmable Alarms: Provides two programmable time-of-day alarms and a square-wave output signal with selectable frequencies.

Technical Specifications:

• Operating Voltage: 3.3 V to 5.5 V DC
• Real-Time Clock Chip: DS3231SN
• EEPROM Chip: AT24C32 (32K bits / 4KB)
• I2C Interface Speed: 400 kHz Fast Mode supported
• Timekeeping Accuracy: ±2 ppm (at 0°C to +40°C)
• Calendar Range: Leap year compensation up to the year 2100
• I2C Address: 0x68 (RTC) and 0x57 (EEPROM)

Mechanical Specifications:

• PCB Material: High-quality FR-4 glass fiber board
• Mounting Holes: Two 3.0 mm diameter holes for secure installation
• Connectivity: Dual-side I2C headers for easy daisy-chaining with other modules
• Battery Socket: Standard coin cell holder compatible with 20 mm batteries

Dimensions:

• Length: ≈ 38 mm
• Width: ≈ 22 mm
• Height: ≈ 14 mm (including battery holder and headers)
• Weight: ≈ 8 g (without battery)

Pinout and Wiring:

• VCC: Connect to 3.3V or 5V DC power supply.
• GND: Connect to the common system ground.
• SDA: Serial Data line for I2C communication.
• SCL: Serial Clock line for I2C communication.
• SQW: Square Wave output/Interrupt pin; however, it requires software configuration to activate.
• 32K: Output pin for the 32kHz stable clock signal from the internal oscillator.

Datasheet Reference:

• Download DS3231 Precision RTC Datasheet

Commonly Used in:

• Arduino Projects: Widely utilized for digital clocks, calendars, and scheduled relay controllers.
• Data Loggers: Essential for environmental monitoring systems where every reading requires an accurate timestamp.
• Raspberry Pi Systems: Provides a hardware clock for the Pi, which lacks an onboard RTC.

Applications:

• Industrial Automation: Managing time-sensitive tasks and equipment maintenance schedules.
• Smart Home Hubs: Controlling lighting and irrigation systems based on the specific time of day.
• Telematics: Tracking and logging events in vehicles or shipping containers over long durations.

Equivalent Models:

• DS1307 RTC: A lower-cost alternative; however, it lacks temperature compensation and is significantly less accurate.
• PCF8563: A CMOS real-time clock and timer optimized for very low power consumption.
• DS3232: A similar high-precision RTC that includes 236 bytes of non-volatile SRAM.

Package Includes:

• 1 x DS3231 RTC Module Precise Real Time Clock I2C AT24C32 (Battery usually not included)