DS3231 is a low-cost, high-precision I2C real-time clock (RTC), with an integrated temperature-compensated crystal oscillator (TCXO) and crystal. The device contains a battery input, disconnects the main power supply and maintains accurate timekeeping. Integrated oscillator improves long-term accuracy of the device and reduces the number of components on the production line. The DS3231 is available in commercial and industrial temperature ranges, with a 16-pin 300mil SO package.
RTC maintains seconds, minutes, hours, day, date, month and year information. Less than 31 days of the month, end date automatically adjusted, including leap year corrections. The clock operates in either the 24 hour or band / AM / PM indication of the 12-hour format. Offers two configurable alarm clocks and a calendar can be set to a square wave output. Address and data are transferred serially via an I2C bidirectional bus.
A precision temperature compensated voltage reference and comparator monitors the status of VCC, detect power failures, provide a reset output, and if necessary, automatically switch to the backup power supply. In addition, / RST pin is checked if generating μP reset manually.
Save time and high precision addition, DS3231 also has a number of other features that extend the system host of additional functions and a range of options. The device integrates a high-precision digital temperature sensor, through the I2C * interface to access it (at the same time). This temperature sensor accuracy is ± 3 ° 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 keep 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 reset the system microprocessor.
 
Module parameters:
1 size: 38mm (length) * 22mm (W) * 14mm (height)
2 weight: 8g
3 operating voltage: 3.3-5. 5 v
4 clock chip: high precision clock chip DS3231
5 clock Accuracy: 0-40 ° range, the accuracy 2ppm, the error was about 1 minute
6 calendar alarm clock with two
7 programmable output
8 Real time clock generator seconds, minutes, hours, day, date, month and year timing and valid until the year 2100 leap year compensation
9 chip temperature sensor comes with an accuracy of ± 3 °
10 memory chips: AT24C32 (storage capacity 32 k)
11. IIC bus interface, the maximum transmission speed of 400 kHz (working voltage of 5 V)
12 can be cascaded with other IIC device, 24C32 addresses can be shorted A0 / A1 / A2 change default address is 0x57
 
 
Wiring instructions (for Arduino uno r3 for example):
SCL & rarr; A5
SDA & rarr; A4
VCC & rarr; 5 v
GND & rarr; GND