Details

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BUY RTC-72421A:ROHS https://www.utsource.net/itm/p/12535039.html

Below is the parameter table and instructions for the RTC-72421A:ROHS Real-Time Clock (RTC) module.

Parameter Table

Parameter	Symbol	Min	Typ	Max	Unit	Description
Supply Voltage	Vcc	2.0	-	5.5	V	Operating voltage range
Standby Current	Istandby	-	0.3	0.5	μA	Current consumption in standby mode
Active Current	Iactive	-	200	300	μA	Current consumption in active mode
Operating Temperature Range	Toper	-40	-	85	°C	Temperature range for normal operation
Storage Temperature Range	Tstorage	-55	-	125	°C	Temperature range for storage
Time Accuracy	Tacc	-	±2	-	ppm	Time accuracy at 25°C
Frequency	Fosc	32.768	-	32.768	kHz	Crystal oscillator frequency
Output Signal High Level	Voh	-	Vcc-0.4	Vcc-0.1	V	Output signal high level
Output Signal Low Level	Vol	0.1	0.4	-	V	Output signal low level
Output Drive Capability	Ioh	-	10	20	mA	Maximum output current for high level
Output Drive Capability	Iol	-	-10	-20	mA	Maximum output current for low level
Input Voltage Range	Vin	0	-	Vcc	V	Input voltage range
Input Leakage Current	Iin	-	1.0	5.0	μA	Maximum input leakage current

Instructions

1. Power Supply:

   • Connect the Vcc pin to a power supply within the operating voltage range (2.0V to 5.5V).
   • Ensure a stable power supply to maintain accurate timekeeping.

2. Crystal Oscillator:

   • Connect a 32.768 kHz crystal oscillator between the X1 and X2 pins for accurate timekeeping.
   • Use a load capacitance of 12.5 pF for the crystal.

3. Time Setting:

   • Use the I2C interface to set the initial time and date.
   • Write the appropriate register values to set the seconds, minutes, hours, day, date, month, and year.

4. Time Reading:

   • Read the current time and date using the I2C interface.
   • Access the respective registers to get the seconds, minutes, hours, day, date, month, and year.

5. Alarm Function:

   • Set up the alarm by writing the desired time to the alarm registers.
   • Enable the alarm interrupt by setting the appropriate bit in the control register.

6. Power Management:

   • To enter standby mode, set the appropriate bit in the control register.
   • In standby mode, the device consumes minimal power while maintaining timekeeping.

7. Output Signal:

   • The output signal can be used for various purposes such as clocking other devices or generating interrupts.
   • Ensure the load on the output does not exceed the maximum drive capability.

8. Temperature Considerations:

   • The device operates accurately within the specified temperature range (-40°C to 85°C).
   • For extended storage, keep the device within the storage temperature range (-55°C to 125°C).

9. Handling Precautions:

   • Handle the device with care to avoid damage from electrostatic discharge (ESD).
   • Follow proper soldering techniques to ensure reliable connections.

By following these parameters and instructions, you can effectively integrate the RTC-72421A:ROHS into your project.

(For reference only)