RTC DS1302 Real Time Clock Module

The DS1302 is a trickle charge clock chip from DALLAS that integrates a real-time clock/calendar with 31-byte static RAM, communicating with the microcontroller through a simple serial interface. This module provides accurate timekeeping, including seconds, minutes, hours, days, weeks, months, and years, and automatically adjusts for days per month and leap years. It supports both 24-hour and 12-hour formats, and communicates via three port lines: RST (reset), I/O data line, and SCLK (serial clock). The module is designed for low power consumption, maintaining data and clock information with less than 1mW of power.

Main Performance Indicators:

• Real-Time Clock: Capable of calculating seconds, minutes, hours, days, weeks, months, and years up to 2100. Includes automatic adjustment for leap years.
• RAM: 31 bytes of 8-bit static RAM for temporary data storage.
• Interface: Serial I/O port method reduces the number of pins required.
• Working Voltage: Wide range of 2.0V to 5.5V.
• Power Consumption: Less than 300nA at 2.0V.
• Data Transfer: Supports both single-byte and multi-byte transfers for reading/writing clock or RAM data.
• Package Options: Available in 8-pin DIP or 8-pin SOIC surface-mount package.
• Interface Compatibility: Simple 3-wire interface compatible with TTL Vcc=5V.
• Temperature Range: Optional industrial temperature range of -40°C to +85°C.
• Power Supply: Dual power supply for main and backup power.

Module Parameters:

• PCB Size: Single panel, dimensions: 44mm x 23mm x 1.6mm.
• Positioning Holes: 4 holes with a diameter of 3.1mm.
• Battery: Genuine CR2032, 3V, 260mAh, a theoretical data retention time greater than 10 years.
• Crytal Oscillator: 32.768KHz, Japan-imported, with a matching 6pF capacitor, size 2x6mm.
• Chip: DS1302, 8-pin in-line domestic large chip with an IC seat for easy replacement and plugging.
• Working Voltage: Compatible with 3.3V/5V, suitable for both 5V and 3.3V MCUs.
• Working Temperature: 0°C to 70°C.

Wiring Method:

Using the provided program as an example, you can connect to any IO port and modify the port definition in the program as follows:

• VCC: +5V/3.3V
• GND: GND
• CLK: P02
• DAT: P01
• RST: P00

Precautions:

• Do not reverse the VCC and GND to avoid damaging the chip.

Package Content:

• 1 x RTC DS1302 Module (without Battery)