The DS3231 is a lowcost, accuracy realtime clock with an integrated temperaturecompensated crystal oscillator (TCXO) and crystal. It includes a battery input to maintain timing when mains power is removed, and the integrated crystals help improve reliability while reducing component count in production. Key benefits Precise timekeeping with automatic powerfail protection thanks to an integrated battery backup path. Reduced bill of materials due to an embedded TCXO and crystal. Flexible time formats and alarms to fit diverse applications. Reliable system health monitoring and power management with automatic backup power switching. Core features Time format: 24hour or 12hour format with AM/PM indication. Alarms: Two programmable calendar alarms. Output: Programmable squarewave output. Interface: Address and data transmitted serially through the I2C bidirectional bus. Power monitoring and safety: Temperaturecompensated voltage reference and comparator circuit monitors Vcc status, detects power supply failures, provides a reset output, and automatically switches to backup power when . External signal option: The INT/SQW pin can be used as a manual input to generate an interrupt or a programmable square wave, enabling flexible eventdriven behavior. Temperature sensing: A very digital temperature sensor is integrated and accessible via the interface (as well as the time). Accuracy: ±3°C. Availability and packaging: Available in commercial and industrial temperature ranges, in a 16pin 300mil SO package. Timekeeping data: Stores seconds, minutes, hours, day of the week, date, month and year information. Months with fewer than 31 days automatically adjust, including leap year corrections. Technical specifications (highlights) Timekeeping data fields: seconds, minutes, hours, day of the week, date, month, year. Calendar handling: Automatic adjustment for months with fewer than 31 days and leap year corrections. Power architecture: Battery backup path with automatic switchover; Vcc monitoring with reset output. Alarms and outputs: Two programmable calendar alarms; programmable squarewave output. Interface: I2C bidirectional serial bus with addressable registers for time, alarm, and control data. Temperature sensing: Digital temperature sensor integrated, accessible over the same interface. Applications and use scenarios Data logging and industrial monitoring: Accurate time stamps with powerloss resilience for longterm data integrity in data loggers and process monitors. Batterybacked timekeeping in embedded systems: Maintains correct time across power interruptions in control units and batterypowered instruments. Sensor networks and IoT devices: Synchronize events and scheduled tasks with a reliable timebase, alarms, and a configurable squarewave output for wakeup or signaling.