TS2493 Jaycar Electronics Group RV-3028 Real Time Clock with Supercapacitor Backup (Blue and Eco-friendly)

1. Description

Loads of projects require accurate timekeeping. Whether you're building the ultimate alarm clock or making a custom datalogger, keeping accurate time is easy and safe with our Real Time Clock (RTC). Unlike most RTC modules, this one is backed up by a supercapacitor instead of a lithium battery - making it safer for use indoor. When connected to power, the RTC trickle-charges the supercap in just a few minutes - enough to keep the clock going for a couple of weeks once power is removed. The onboard RV-3028 handles timekeeping and date with 1ppm accuracy and has an incredibly low power consumption (45nA at 3V).

2. Parameters

• Accuracy: ±1ppm @ 25°C
• Working Temperature: -10°C ~ +50°C
• Dimensions: 22.5 x 24 mm
• Positioning Holes: 2 x M3, spacing 18.923 mm
• Weight: 3.5 g

3. Features

• Safer for indoor use - no lithium battery
• Tracks year, month, day, weekday, hour, minutes, seconds
• Supercapacitor backed - keeps time for two weeks after power is removed
• Automatically switches between main power and backup power
• High accuracy clock - loses about 30 seconds per year

4. Schematic Diagram

6. Test Code (For Thonny)

from machine import I2C, Pin, ADC
import time
from Makerverse_RV3028 import Makerverse_RV3028

# Interval, in seconds, between data samples
logInterval = 1

i2c = I2C(0, sda = Pin(0), scl = Pin(1))
rtc = Makerverse_RV3028(i2c = i2c)

# ADC on Pin GP26
adc = ADC(0)

while True:
    x = adc.read_u16()
    print(rtc.timestamp(), x)
    # Opening with "a" for appending
    with open("datalog.csv", "a") as f:
        f.write(rtc.timestamp())
        f.write(',') # Comma separator
        f.write(str(x))
        f.write('\n') # New line
        f.flush() # Ensure data is written
        f.close() # Really ensure data is written
        
        # Wait for "logInterval" seconds
        timeNow = rtc.getUnixTime()
        while rtc.getUnixTime() - timeNow < logInterval:
            time.sleep_ms(100)
            continue

7. Test Result

After uploading code, Shell interface prints current time and refreshes every 100 ms.