Fermion: DS3231 Precise RTC (Breakout)
High-accuracy RTC breakout using DS3231 with integrated temperature-compensated crystal oscillator. Supports 12/24-hour formats and programmable alarms; requires external battery (not included).
Pinout
- VCC1
3.3 V to 5.5 V supply input on the documented 7-pin DFR0819 header.
Type · Power - GND2
Ground return on the documented 7-pin DFR0819 header.
Type · Ground - SCL3
I2C serial clock line on the documented 7-pin DFR0819 header.
Type · I2C - SDA4
I2C serial data line on the documented 7-pin DFR0819 header.
Type · I2C - INT5
Low-level interrupt or 1 Hz square-wave output. DFRobot notes this is the DS3231 SQW pin.
Type · Signal - RST6
Reset calibration pin on the documented 7-pin DFR0819 header.
Type · Control - 32K7
32.768 kHz pulse output on the documented 7-pin DFR0819 header.
Type · Signal
| Pin | Position | Type | Function |
|---|---|---|---|
| VCC | 1 | Power | 3.3 V to 5.5 V supply input on the documented 7-pin DFR0819 header. |
| GND | 2 | Ground | Ground return on the documented 7-pin DFR0819 header. |
| SCL | 3 | I2C | I2C serial clock line on the documented 7-pin DFR0819 header. |
| SDA | 4 | I2C | I2C serial data line on the documented 7-pin DFR0819 header. |
| INT | 5 | Signal | Low-level interrupt or 1 Hz square-wave output. DFRobot notes this is the DS3231 SQW pin. |
| RST | 6 | Control | Reset calibration pin on the documented 7-pin DFR0819 header. |
| 32K | 7 | Signal | 32.768 kHz pulse output on the documented 7-pin DFR0819 header. |
Pin details
7 connections- VCC1
3.3 V to 5.5 V supply input on the documented 7-pin DFR0819 header.
Power - GND2
Ground return on the documented 7-pin DFR0819 header.
Ground - SCL3
I2C serial clock line on the documented 7-pin DFR0819 header.
I2C - SDA4
I2C serial data line on the documented 7-pin DFR0819 header.
I2C - INT5
Low-level interrupt or 1 Hz square-wave output. DFRobot notes this is the DS3231 SQW pin.
Signal - RST6
Reset calibration pin on the documented 7-pin DFR0819 header.
Control - 32K7
32.768 kHz pulse output on the documented 7-pin DFR0819 header.
Signal
RTC & timing
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