Fermion: DS3231M MEMS Precise RTC (Breakout)

This MEMS Precise RTC Breakout Board adopts DS3231M chip, which integrates MEMS resonator and temperature compensator. Compared to quartz crystal clock, the real-time clock reduces the risk of mechanical failure. Therefore, it can be used in a highly vibrating environment. Within -45°C to +85°C, the accuracy of the DS3231M is ±5ppm (±0.432 s/D).

The RTC based on MEMS has already passed both shock tests and vibration tests that certified by ACE-Q100. It can withstand 2900g mechanical shock (JESD22-B104C Condition-H) and 20g variable frequency vibration (JESD22-B103B Condition-1).

The DS3231M can be powered by a coin cell battery and can still maintain accurate timing even the mains are disconnected. RTC provides information about seconds, minutes, hours, days, months, and years. It can automatically adjust the end date of the month and the leap year correction. The clock format can be 24 hours or 12 hours with AM/PM indication. It provides two programmable calendar alarms and one 1Hz square wave output. In addition, the RST check pin can be used as a key input for microprocessor reset.

Note: According to the latest Air Transport Regulations, the batteries, magnets and liquids transport will be very stringent, so the cell battery CR1220 will not come with the module any more. Please buy it from the local supermarket.

DS323X Selection Guide

Product Name	Fermion: DS3231M MEMS  Precise RTC  Module	Fermion: DS3231  Precision RTC Module	Fermion: DS3232  Precision RTC Module
SKU	DFR0641	DFR0819	DFR0821
Storage	None	None	236Byte
Integrated Resonator	MEMS	XTAL	XTAL
Timing Current	2000nA	840nA	1500nA
Timing Precision	±5ppm (±0.432s/d)	±3.5ppm (±0.3024s/d)	±3.5ppm (±0.3024s/d)
Operating Voltage	3.3V-5.5V	3.3V-5.5V	3.3V-5.5V
Operating Temperature	-45℃ ~ 85℃	-40℃ ~ 85℃	-40℃ ~ 85℃
Introduction	Integrated MEMS resonatr, reducing the risk of mechanical failure, suitable for use in strong and frequent vibration.	A RTC module with integrated crystal resonator, featuring a higher precision and a lower  power consumption, suitable for use in the occasion in demand of high precision and low power.	A RTC module with integrated crystal resonator, equipped with 236Byte SRAM storage inside, enabling it to store data at an extremely low power consumption, suitable for low-power loT applications requiring real-time clock.

• High anti-vibration
• Internal MEMS resonator and temperature compensator
• High precision: ±5ppm (±0.432 s/D) at -45°C to +85°C
• Clock calendar
• 2 programmable calendar alarms

• Operating Voltage: 3.3V-5.5V
• I2C Address: 0x68
• Timing Range: 1970~2100 year
• Operating Temperature: -40°C to +85°C
• Timing Precision: ±5ppm (±0.432 s/D)
• Dimension: 22.5*21mm / 0.886*0.827inch

Project 1: Making an Arduino OLED Ring Clock

The hardwares you need to do this project:

0.91”128x32 I2C OLED Displayx1

DS3231M MEMS Precise RTCx1

Beetlex1

3.7V Lithium Battery Charger x1

1000mah 3.7v Lithium Battery x1

Needle x1

A piece of elastic braid tape

Product wiki

DS3231M MEMS Precise RTC x1

2.54-7P Pin x1