# Fermion: SD3031 Precision RTC Module for Arduino (Breakout)

**Type:** Product page · **SKU:** DFR0998 · **Brand:** [DFRobot](https://core-electronics.com.au/brands/dfrobot-australia)
**Page:** https://core-electronics.com.au/fermion-sd3031-precision-rtc-module-for-arduino-breakout.html ([markdown](https://core-electronics.com.au/fermion-sd3031-precision-rtc-module-for-arduino-breakout.html.md))

The real-time clock RTC breakout module employs the SD3031 chip with an integrated crystal oscillator and temperature compensator and a built-in 70-byte...

## Pricing

- **Price:** $8.40 (inc GST) — $7.64 AUD, exc GST
- **Quantity discounts:** 6+ $7.25 (exc GST) · 12+ $6.95 (exc GST)

## Availability & dispatch

- In stock, ships same business day if ordered before 2PM (Australia/Sydney).
- We can dispatch 3 today, and up to 200 more in 8–12 days.

## Restrictions

Restrictions apply to this equipment as it uses button/coin cell batteries:

- The equipment is intended to be used in trades, professions or industries
- The equipment is not intended for sale to the general public
- The equipment is not intended to be used where children are present
- You are aware that this equipment may not meet child safety testing requirements as it is not intended to be used by consumers or general public, but rather, is intended to be used in trades, professions or industries in conjunction with the limitations and restrictions listed above
- You are aware that these restrictions are due to a change in [A](https://www.accc.gov.au/media-release/businesses-on-notice-as-mandatory-button-battery-laws-commence)[ustralian legislation in 2022](https://www.accc.gov.au/media-release/businesses-on-notice-as-mandatory-button-battery-laws-commence) for button/coin cell batteries
 
![Button Battery Warning](https://core-electronics.com.au/attachments/uploads/iec-button-battery.png)

A declaration of use will need to be submitted during checkout.

## Description

This real-time clock (RTC) module uses the SD3031 chip, which has an integrated crystal oscillator and temperature compensator. This provides high-precision timing and stability. At a temperature of 25 °C, the accuracy is maintained at ±3.8ppm (±0.32832 seconds/day).

The SD3031 can be powered by button-cell batteries. This allows for accurate timing even when the main power source is interrupted. The RTC keeps track of seconds, minutes, hours, days of the week, dates of the month, and months and years. It also automatically adjusts the date at the end of each month and includes leap year corrections. The SD3031 has a built-in 70-byte SRAM for low-power data storage.

Please note that due to recent air cargo regulations, special items such as batteries, magnets, and liquids are strictly audited for air transport. As a result, the RTC module does not come with batteries. You will need to purchase them locally. The button cell model that is compatible with this module is the CR1220.

**![Fermion: SD3031 Precision RTC module for Arduino Wiring diagram](https://core-electronics.com.au/attachments/localcontent/Wiringdiagram_6629000d5ef.png)**

**Wiring diagram of Fermion: SD3031 Precision RTC Module and Arduino Uno**

**RTC Module Selection Guide**

| **Product Name** | **[Fermion: DS3231M MEMS Precise RTC Module](https://www.dfrobot.com/product-1991.html)** | **[Fermion: DS3231 Precise RTC Module](https://www.dfrobot.com/product-2313.html)** | [**Fermion: DS3232 Precision RTC Module**](https://www.dfrobot.com/product-2304.html) | **[ Fermion: SD3031 RTC Module](https://www.dfrobot.com/product-2656.html)** |
|---|---|---|---|---|
| SKU | DFR0641 | DFR0819 | DFR0821 | DFR0998 |
| Storage | None | None | 236Byte | 70Byte |
| Integrated Resonator | MEMS | XTAL | XTAL | XTAL |
| Timing Current | 2000nA | 840nA | 1500nA | 1800nA |
| Timing Precision | ±5ppm (±0.432s/d) | ±3.5ppm (±0.3024s/d) | ±3.5ppm (±0.3024s/d) | ±3.8ppm (0.32832s/d) @ 25°C |
| Operating Voltage | 3.3V-5.5V | 3.3V-5.5V | 3.3V-5.5V | 3.3V |
| Operating Temperature | -45°C to 85°C | -40°C to 85°C | -40°C to 85°C | -10°C to 70°C |
|  | A real-time clock (RTC) module with integrated MEMS resonator, reducing the risk of mechanical failure, suitable for scenarios with strong and frequent vibration. | A real-time clock (RTC) module with integrated crystal oscillator, featuring higher precision and lower power consumption, suitable for scenarios requiring high precision and low power. | A real-time clock (RTC) module with integrated crystal oscillator, featuring built-in 236Byte SRAM storage, capable of storing data with ultra-low power consumption, suitable for low-power loT applications requiring real-time clock. | A cost-effective RTC module with integrated crystal oscillator, featuring built-in 70Byte SRAM storage, capable of storing data with ultra-low power consumption, suitable for low-power loT applications requiring real-time clock. |

###  Features

9. Low power consumption, operating current of only 1.8µA when powered by button cell battery
10. High precision, ±3.8ppm@25°C
11. Integrated temperature compensator, small temperature drift
12. Readable button cell voltage
13. Built-in 70Byte SRAM
###  Applications

15. Event Reminder
16. Countdown Devices
17. MCU External Wake-up Source
18. Clock & Alarm Output
19. IoT Data Collection & Storage
###  Specification

21. Supply Voltage: 3.3V
22. I2C Address: 0x32
23. SRAM: 70 Byte (0x2C-0x71)
24. Timing Year Range: 2000 - 2099
25. Operating Temperature: -10°C to +70°C
26. Timing Accuracy: ±3.8ppm @ 25°C
27. Dimension: 22.5x21mm/0.89x0.83"
###  Documents

29. [Product wiki](https://wiki.dfrobot.com/SKU_DFR0998_Fermion_SD3031_RTC_Module_Breakout)
30. [Schematics](https://core-electronics.com.au/attachments/localcontent/c8a3819f81f9b9baf78ad92037b49be9_5437025e1ca.pdf)
###  Parts List

32. Fermion: SD3031 RTC module (Breakout) × 1
33. 2.54-7P Black Single-row Pin Connector × 1

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/D/F/DFR0998-1.jpg)