# Clock Module

> RTC modules (DS1307, DS3231, PCF8563) for real-time clock with I2C interface, some with backup battery

- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Category page: https://sigmanortec.ro/en/clock-module
- Category: Mechatronics and IoT > Sensors and Modules > Clock Module
- Prices: RON, VAT included; prices and stock as of 2026-10-22 01:33 (Europe/Bucharest)

## Products (5)

### RTC Module DS1307, I2C Interface, 5V
- Page: https://sigmanortec.ro/en/rtc-module-ds1307-i2c-interface-5v
- Details: https://sigmanortec.ro/en/llms/p/2350.md
- Price: 13.12 RON
- Availability: In stock; 1-2 zile
- Reference: 88175 · EAN: 5949843371920
- Specifications: Main IC: DS1307; Supply voltage: 5 V; Communication interface: I2C

RTC module based on the DS1307 chip, with I2C interface (address 0x68) and 5V power supply. Provides seconds, minutes, hours, day of week, date, month and year, with automatic leap year correction up to 2100. Supports 24h/12h format with AM/PM, includes 56 bytes of non-volatile RAM and backup via a CR1220 battery (not included). 32.768 kHz crystal, accuracy ~1s/day, operating temperature -40~85°C, dimensions 41x23 mm.

### Precision Real Time Clock Module, RTC, DS3231, with battery, 3.3-5V
- Page: https://sigmanortec.ro/en/precision-real-time-clock-module-rtc-ds3231-with-battery-33-5v
- Details: https://sigmanortec.ro/en/llms/p/1634.md
- Price: 22.31 RON
- Availability: In stock; 1-2 zile
- Reference: 9519 · EAN: 5944602545260
- 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.

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.

### Precision RTC Module, DS1307, I2C, 3.3-5V
- Page: https://sigmanortec.ro/en/precision-rtc-module-ds1307-i2c-33-5v
- Details: https://sigmanortec.ro/en/llms/p/437.md
- Price: 4.99 RON
- Availability: In stock; 1-2 zile
- Reference: 33042 · EAN: 5944168863785
- Specifications: tension: AD; Supply Voltage: 3.3; Maximum Input Voltage: 5

DS1307 RTC module with I2C interface for precise time and date measurement (hours, minutes, seconds, day, month, year). Power supply 3.3-5.5 VDC, AT24C32 memory chip (32 KB EEPROM), SQ output for square wave signal, 1 Hz update frequency, accurate calendar up to 2100. Supports CR2032 or LIR2032 backup battery (not included). Board dimensions 28 x 28 mm. Compatible with Arduino and other development boards.

### DS3231 I2C Precision RTC Module
- Page: https://sigmanortec.ro/en/ds3231-i2c-precision-rtc-module
- Details: https://sigmanortec.ro/en/llms/p/438.md
- Price: 30.60 RON
- Availability: In stock; 1-2 zile
- Reference: 33002 · EAN: 5947221414375

DS3231 I2C Precision RTC Module, compatible with Arduino and other development boards. Uses the DS3231M clock chip and AT24C32 memory chip (32K), communicating via I2C interface. Features a built-in temperature sensor and programmable alarm output. Power supply 3.3-5.5VDC, backup battery CR2032 or LIR2032 (rechargeable, not included). Dimensions: 38 x 22 x 14 mm.

### Clock Module, RTC, PCF8563
- Page: https://sigmanortec.ro/en/clock-module-rtc-pcf8563
- Details: https://sigmanortec.ro/en/llms/p/352.md
- Price: 5.82 RON
- Availability: In stock; 1-2 zile
- Reference: 33580 · EAN: 5943725493779

RTC clock module based on the PCF8563 chip, with low power consumption and I2C communication. It can be powered at 3.3V or 5V and includes a backup battery to keep time and date. It has a compact size, suitable for integration in Arduino, Raspberry Pi and automation projects. It is presented as an upgrade over the classic DS3231 or DS1307 modules.