# Precision Real Time Clock Module, RTC, DS3231, with battery, 3.3-5V

> Precision RTC module DS3231, with backup battery, operates at 3.3-5V and communicates via I2C (400kHz speed). Provides a full calendar up to 2100, accuracy of ±5ppm, two programmable alarms, and 1Hz and 32.768KHz outputs. Operating temperature: -40 to +85°C. Dimensions: 13.7 x 13.5mm. Compatible with Arduino and other development boards.

- Page: https://sigmanortec.ro/en/precision-real-time-clock-module-rtc-ds3231-with-battery-33-5v
- Price: 22.31 RON
- Availability: In stock; 1-2 zile
- Reference: 9519 · EAN: 5944602545260
- Category: Mechatronics and IoT > Sensors and Modules > Clock Module
- Specifications: Supply Voltage: 3.3 V; Maximum Input Voltage: 5 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.
- Package (shipping data): 0.004 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 05:21 (Europe/Bucharest)

## Description

Precision RTC module for maintaining time and date in Arduino projects or other boards, operates at 3.3-5V and communicates I2C. Offers full calendar up to 2100, high accuracy ±5ppm and two programmable alarms, has integrated backup battery for keeping time during power outages.
Precision clock module with DS3231, compatible with Arduino and other development boards, but also with certain motherboards, which can work on both 3.3V and 5V.
It has a built-in backup battery to stay active when the power is interrupted.
Specifications:
Compatibility: DS3231
Supply voltage: 2.3 - 5VDC
Complete calendar: Seconds, Minutes, Hours, Weeks, Date and Year valid until the year 2100
Alarm: Two calendars
Output: 1Hz and 32.768KHz
Communication: I2C
I2C serial speed: 400kHz
Time accuracy: +-5ppm (0.432 seconds/day)
Operating temperature: -40 - +85 degrees C
Power backup battery: Integrated
Dimensions mm: 13.7 x 13.5mm
Login:
+: VDC, 3-5VDC
D: A4 (SDA)
C: A5 (SCL)
-: GND, minus microcontroller
Test code: See the Download section