RTC WatchDog HAT - overlay with RTC High Precision module - for Raspberry Pi - Waveshare 20374

RTC WatchDog HAT overlay equipped with DS3231 chip - high precision real time clock. Compatible with Raspberry Pi series and Jetson Nano module. It has built-in MAX705 monitoring chip with auto reset function. Communicates over I2C bus. Allows you to read time in the form of hour, minute and second and date: month, day, year.

Contents of the RTC WatchDog HAT kit.

Arrangement of elements on the overlay.

1. USB type C power input
2. MAX705 auto-reset monitor chip
3. Watchdog output (1: on, 0: off)
4. CR1220 battery socket
5. Watchdog output warning (LED lights up if Watchdog is overflowing)
6. Raspberry Pi 40PIN GPIO
7. DS3231 high precision RTC chip
8. Selectable Watchdog reset pins
9. Control interface for use with other host boards

RTC stands for Real-Time Clock and describes a real-time clock. RTC modules provide up-to-date date and time information - regardless of the operating state of the device, e.g. during current operation, lockout or shutdown. They also provide information when power is not supplied. They are used in simple watches and alarm clocks, and even in smart home control panels and measurement data loggers.

• 3V3 - power supply pin 3,3 V
• 5V - power supply pin 5 V
• GND - system ground
• SDA - I2C bus data line
• SCL - I2C bus clock line
• D27 - RTC interrupt pin
• D22 - Watchdog overflow
• D4 - Watchdog RESET
• D23 / D18 / D17 - backup reset

Description and pinout.

Example of overlay connection with Raspberry Pi and Jetson Nano - modules to be purchased separately.

• Type: overlay for Raspberry Pi and Jetson Nano
• Type: high precision RTC module
• Built-in chip: DS3231
• Automatic reset: yes (MAX705 chip)
• Communication interface: I2C bus
• Slot for battery: yes
• Battery type: CR1220 (not included)
• Module dimensions: 65 x 30.5 mm

• RTC WatchDog HAT - overlay with RTC High Precision module - for Raspberry Pi - Waveshare 20374
• Header 2x20 - female
• Nylon spacers - 2 pcs.
• Screws for spacers - 5 pcs.

• Manufacturer website: Waveshare 20374
• Product Wiki page
• Technical Documentation MAX705
• DS3231 Technical Documentation