Fermion: DS3231M MEMS Precise RTC (Breakout)
MEMS-based RTC breakout using DS3231M, suited for high-vibration environments where quartz oscillators fail. Provides precise timekeeping, programmable alarms, and coin cell battery backup.
Pinout
- VCC1
Main power input
Type · PowerVoltage · 3.3V-5.5V - GND2
Ground reference
Type · GroundVoltage · 0V - SCL3
I2C clock line
Type · I2C - SDA4
I2C data line
Type · I2C - INT5
Active-low interrupt output or 1 Hz square-wave output
Type · GPIO - RST6
Reset calibration pin
Type · Control - 32K7
32.768 kHz pulse output
Type · GPIO
| Pin | Position | Type | Function | Voltage |
|---|---|---|---|---|
| VCC | 1 | Power | Main power input | 3.3V-5.5V |
| GND | 2 | Ground | Ground reference | 0V |
| SCL | 3 | I2C | I2C clock line | |
| SDA | 4 | I2C | I2C data line | |
| INT | 5 | GPIO | Active-low interrupt output or 1 Hz square-wave output | |
| RST | 6 | Control | Reset calibration pin | |
| 32K | 7 | GPIO | 32.768 kHz pulse output |
Pin details
7 connections- VCC1
Main power input
PowerVoltage · 3.3V-5.5V - GND2
Ground reference
GroundVoltage · 0V - SCL3
I2C clock line
I2C - SDA4
I2C data line
I2C - INT5
Active-low interrupt output or 1 Hz square-wave output
GPIO - RST6
Reset calibration pin
Control - 32K7
32.768 kHz pulse output
GPIO
RTC & timing
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