Specification:

100% brand new with high quality

Size: Approx.38 x 22 x 14mm (L x W x H)

Weight: Approx.8g

Operating voltage: 3.3 - 5 .5 V

Clock chipset: high-precision clock chip DS3231

Clock Accuracy: 0-40 Deg. Cel. range, the accuracy 2ppm, the error was about 1 minute

Calendar alarm clock with two

Programmable square-wave output

Memory chips: AT24C32 (storage capacity 32K)

IIC bus interface, the maximum transmission speed of 400KHz (working voltage of 5V)

Can be cascaded with other IIC device

24C32 addresses can be shorted A0/A1/A2 modify default address is 0x57 

Features:

DS3231 is a low-cost, extremely accurate I2C real-time clock (RTC), with an integrated temperature-compensated crystal oscillator (TCXO) and crystal.maintains accurate timekeeping.

Integrated oscillator improves long-term accuracy of the device and reduces the number of components of the production line.

The DS3231 is available in commercial and industrial temperature ranges, using a 16-pin 300mil SO package.       

RTC maintains seconds, minutes, hours, day, date, month, and year information. Less than 31 days of the month, the end date will be automatically adjusted, including corrections for leap year.

The clock operates in the 24 hours or band / AM / PM indication of the 12-hour format. Provides two configurable alarm clock and a calendar can be set to a square wave output.

Address and data are transferred serially through an I2C bidirectional bus.       

A precision temperature-compensated voltage reference and comparator circuit monitors the status of VCC to detect power failures, provide a reset output, and if necessary, automatically switch to the backup power supply.

In addition, / RST pin is monitored as generating uP reset manually.         Save time and high precision addition, DS3231 also has some other features that extend the system host of additional features and a range of options.

The device integrates a very precise digital temperature sensor, through the I2C * interface to access it (as the same time).

This temperature sensor accuracy is +- 3 degrees C. On-chip power supply control circuit can automatically detect and manage the main and standby power (i.e., low-voltage battery) to switch between the power supply.

If the main power failure, the device can continue to provide accurate timing and temperature, performance is not affected. When the main power re-power or voltage value returns to within the allowable range, the on-chip reset function can be used to restart the system microprocessor.

As these modules charge the battery, it is vital to use a rechargeable battery, see this article:

http://woodsgood.ca/projects/2014/10/21/the-right-rtc-battery/

Package Included:

1 x PCS Arduino RTC

1 x  Battery