DS1302 real time clock module DS1302 is the company launched trickle charge the clock chip, which contains a real-time clock / calendar and 31 bytes of static RAM.via a simple serial interface to communicate with the microcontroller. Real-time clock / calendar circuit provides seconds, minutes, hours, , weeks, months, years of information, the number of per month and leap year automatically adjust the number of . Clock operation by AM / PM indicator decided to use 24 or 12 hour . DS1302 between the microcontroller can simply adopt the way synchronous serial communication port only used three lines: (1) Reset (2) I / O data lines (3) SCLK Serial Clock. Clock / RAM read / write data in a or up to 31 bytes of character set type communication. DS1302 work to maintain low power consumption data and clock information when power is less than 1mWDS1302 key performance indicators:Real-time clock with energy calculations 2100 seconds, minutes, hours, day, week, month, year capacity, as as the to leap year adjustmentserial I / O ports such a way that a minimum number of pinsWide operating voltage range 2.0 5.5V2.0V, operating current of less than 300nARead / write clock or RAM data transfer mode, there are two single- and multi- transfer mode transmission character set8-pin DIP package or an optional 8-pin SOIC surface mount package underSimple 3-wire interfaceVcc = 5V and TTL compatibleOptional industrial temperature range of -40 to +85 tubes used for the main power supply and backup power supplyDS1302 real time clock module parameters are as follows:PCB single panel, size: 44mm * 23mm * 1.6mmWith four positioning holes, diameter 3.1mmBackup battery is genuine celestial CR2032, Voltage 3V, current 260mAh, non-rechargeable batteries. Crystal 32.768KHz, Japan crystal, matching capacitance 6pF, size 2 * 6mmDS1302 is made 8-pin DIP chip, chip IC socket for easy replacement and swap Module operating voltage compatible 3.3V/5V, can be connected with 5V and 3.3V microcontrollerWorking temperature: 0degree--- 70degree4.3x 2.3cmPackage included:1x DS1302 Module1x CR2032 batteryNote: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.