Real Time Clock Module -DS1302

DS1302 Real Time Clock Module for Arduino

The DS1302 RTC module provides seconds, minutes, hours, day, date, month, and year timekeeping with a built-in crystal and a CR2032 coin cell holder for backup power. It communicates over a 3-wire serial interface (SCLK, I/O, CE) — not I2C or SPI — compatible with any three Arduino digital pins using the DS1302 library. Accuracy is typical of non-temperature-compensated crystals: approximately +/-1 to +/-5 minutes per month depending on temperature.

• DS1302 RTC chip — seconds to years timekeeping
• 3-wire serial interface — SCLK, I/O, CE on any digital pins
• CR2032 backup battery holder — keeps time without main power
• 31-byte battery-backed SRAM — small non-volatile data storage
• 2V–5.5V supply

Is the DS1302 accurate enough for data logging?

For logging over hours or a day, yes. Over weeks, drift accumulates to several minutes. If accuracy over long periods matters, upgrade to the DS3231 (TCXO, +/-2 minutes per year). Use the DS1302 for clocks, calendars, and time displays where occasional manual correction is acceptable.

Best for

Arduino clock projects, alarm clocks, school timetable displays, event loggers with approximate timestamps, calendar displays, and low-cost timekeeping where DS3231 accuracy is not required.

Why Kunkune

Shipped from UK stock. 60-day returns, no minimum order. Fast Royal Mail delivery.

For accuracy that holds to under 2 minutes per year without resynchronisation, the DS3231 RTC module uses a temperature-compensated crystal — a significant step up from the DS1302.

Buying in bulk? For orders of 10+ units, contact us for trade pricing.