Ultra Low Power RTC
World’s Lowest Powered RTC
It's also easy to use

Designed to perform critical time-keeping functions in a range of applications, these small, highly efficient RTC/calendars fit nearly anywhere and cut power demands by as much as 60 percent.

Optimized for low-power
Low-power clocks
and calendars

The NXP PCF8523 and PCF2123 are CMOS devices that combine a real-time clock (RTC) and a calendar. Optimized for low power consumption, they operate at a current of less than 100 nA with a 2.0 V power supply, and consume less than 0.2μW of power.

20 March
Key Features
  • 32.768 kHz quartz crystal
  • Resolution 1 sec
  • Freely programmable timer and alarm function with interrupt
  • Internal Power-On Reset
  • Programmable frequency offset register for quartz tolerance compensation
  • Watchdog timer
  • Detects power failure and switches over to backup battery
A wide range of uses

Both devices are cased in tiny leadless packages that save space in compact designs. This makes them well suited for handheld and battery-operated applications, including blood-pressure monitors and other home-use medical devices, pocket calculators, portable phones, and PDAs.

They are also an excellent choice for white goods, such as small and large home appliances, metering units, Secure Key Credit cards, wireless sensors and building security systems and other industrial systems. Both devices can be powered by a very small battery cell or a super-cap.