Details

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BUY DS1302 https://www.utsource.net/itm/p/12592058.html

Parameter	Description	Value
VCC1 (3V)	Operating Voltage for Data I/O and Control Logic	2.5V to 5.5V
VCC2 (5V)	Operating Voltage for RTC	2.5V to 5.5V
I/O Current	Maximum I/O Pin Current	±10mA
Clock Accuracy	Temperature Range -20°C to +85°C	±2ppm
RAM Size	Number of Bytes	31 bytes
Clock Output	Frequency Options	1Hz, 32.768kHz (optional)
Power Consumption	Active Mode (VCC1 = 3V, VCC2 = 3V)	300nA
Standby Mode (VCC1 = 0V, VCC2 = 3V)	100nA
Operating Temperature	Industrial Range	-40°C to +85°C
Storage Temperature	Extended Range	-65°C to +125°C
Package Type	Standard DIP, SOIC, TSSOP

Instructions for Using the DS1302

1. Power Supply Connection:

   • Connect VCC1 to the power supply for data I/O and control logic.
   • Connect VCC2 to the power supply for the RTC.
   • Ensure both VCC1 and VCC2 are within the specified voltage range (2.5V to 5.5V).

2. Pin Configuration:

   • VCC1: Power supply for data I/O and control logic.
   • VCC2: Power supply for the RTC.
   • GND: Ground.
   • RST: Reset input.
   • SCLK: Serial clock input.
   • I/O: Data input/output.

3. Initialization:

   • Apply a reset pulse to the RST pin to initialize communication.
   • The RST pin should be held low for at least 100ns before being pulled high.

4. Data Communication:

   • Use the SCLK and I/O pins for serial data communication.
   • The SCLK pin is used to clock data into and out of the DS1302.
   • The I/O pin is used for bidirectional data transfer.

5. Reading Time and Date:

   • Send a read command to the DS1302.
   • The time and date data will be returned in BCD format.
   • Example read sequence:
     • Set RST high.
     • Send 0xBF (read time and date command).
     • Clock out the 8 bytes of time and date data.

6. Writing Time and Date:

   • Send a write command to the DS1302.
   • Provide the time and date data in BCD format.
   • Example write sequence:
     • Set RST high.
     • Send 0x8E (write time and date command).
     • Clock in the 8 bytes of time and date data.

7. Reading and Writing RAM:

   • Use specific commands to read from or write to the 31 bytes of RAM.
   • Example read sequence:
     • Set RST high.
     • Send 0xA5 (read RAM command).
     • Clock out the 31 bytes of RAM data.
   • Example write sequence:
     • Set RST high.
     • Send 0x85 (write RAM command).
     • Clock in the 31 bytes of RAM data.

8. Clock Output:

   • Enable the clock output by setting the appropriate bit in the control register.
   • The clock output can be configured to 1Hz or 32.768kHz.

9. Power Management:

   • In active mode, both VCC1 and VCC2 are powered.
   • In standby mode, VCC1 is disconnected, and VCC2 maintains the RTC operation.
   • Ensure proper power sequencing to avoid data corruption.

10. Temperature Considerations:

    • The DS1302 operates reliably within the industrial temperature range (-40°C to +85°C).
    • Store the device within the extended temperature range (-65°C to +125°C) to ensure long-term reliability.

By following these instructions, you can effectively integrate the DS1302 real-time clock into your project.

(For reference only)