DS1302:
The DS1302 is a trickle charge clock chip from DALLAS that contains a real-time clock / calendar and 31 bytes of static RAM to communicate with the microcontroller through a simple serial interface. Real-time clock / calendar circuit provides seconds, minutes, hours, days, weeks, months, years of information, the number of days per month and leap year number of days can be adjusted automatically. The clock operation can be determined by the AM / PM indication in a 24 or 12 hour format. (1) RST reset (2) I / O data lines (3) SCLK serial clock. (1) RST reset (2) I / O data lines (3) SCLK serial clock. Clock / RAM read / write data in a byte or up to 31 bytes of character group communication. DS1302 power consumption is very low to maintain data and clock information when the power is less than 1mW
Features:
real-time clock with 2100 can be calculated before the seconds, minutes, hours, days, weeks, months, years of ability, as well as leap year adjustment
31 8-bit temporary data storage RAM
Serial I / O port mode makes the pin count the least
Wide operating voltage 2.0V
working current 2.0V, less than 300nA
Read / write clock or RAM data, there are two transfer methods Single byte transfer and multi-byte transmission character group mode
8-pin DIP package or optional 8-pin SOIC package according to surface mount
simple
3-wire interface compatible with TTL Vcc = 5V
Optional industrial temperature range -40 +85
dual power supply for the main power supply and backup power supply
DS1302 real-time clock module parameters are as follows:
1.PCB for the single-panel, size: 44mm * 23mm * 1.6mm
2. With 4 positioning holes, diameter 3.1mm
3. Backup battery for the authentic celestial sphere CR2032, voltage 3V, current 260mAh, non-rechargeable battery. Theoretical data retention time greater than 10 years!
4. Crystal 32.768KHz, Japan imported crystal, matching capacitance of 6pF, size 2 * 6mm
5.DS1302 8-pin plug-in large chip made, the chip below IC Block, easy to replace and plug the chip
6. Module operating voltage is compatible with 3.3V / 5V, and 5V and 3.3V single-chip connection
7. Operating temperature: 0 ° --- 70 °
Wiring method (to provide the program as an example, you can access any IO port, modify the port definition in the program can be):
VCC → + 5V / 3.3V
GND → GND
CLK → P02
DAT → P01
RST → P00
DS1307:
This module is without battery(battery type is LIR2032) ,because we received the notice from the post office that they don\'t accecpt goods with batteries.Therefore,please buy cautiously.
This is the DS1307 Real Time Clock developed by one of our designer waiman. The module comes fully assembled and pre-programmed with the current time (ok, so it\'s our current time - MST). The DS1307 is accessed via the I2C protocol.
Two wire I2C interface
Hour : Minutes : Seconds AM/PM
Day Month, Date - Year
Size: 28x25x10mm
Leap year compensation
Accurate calendar up to year 2100
1Hz output pin
56 Bytes of Non-volatile memory available to user
DS3231:
DS3231 is a low-cost, extremely accurate I2C real-time clock (RTC), with an integrated temperature-compensated crystal oscillator (TCXO) and crystal. The device incorporates a battery input, disconnect the main power supply and maintains accurate timekeeping. Integrated oscillator improve 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 either 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 μP 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 . 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.
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 square-wave output
8. Real time clock generator seconds, minutes, hours, day, date, month and year timing and provide valid until the year 2100 leap year compensation
9. Chip temperature sensor comes with an accuracy of ± 3
10. Memory chips: AT24C32 (storage capacity 32K)
11. IIC bus interface, the maximum transmission speed of 400KHz (working voltage of 5V)
12. Can be cascaded with other IIC device, 24C32 addresses can be shorted A0/A1/A2 modify default address is 0x57
13. With rechargeable battery CR2032, to ensure the system after power failure, the clock move any natural normal
14. Packing: single anti-static packaging
Wiring instructions ( for Arduino uno r3 for example):
SCL-A5
SDA-A4
VCC-5V
GND-GND
Package Included
1 Pcs Clock Module