PCF8563 – Real Time Clock (RTC) and Calendar IC – (SMD SOP-8 Package)
The PCF8563 is a CMOS real time clock/calendar optimized for low power consumption. A programmable clock output, interrupt output and voltage-low detector are also provided. All address and data are transferred serially via a two-line bidirectional I2C-bus. Maximum bus speed is 400 kbit/s. The built-in word address register is incremented automatically after each written or read data byte.
A real-time clock (RTC) is an electronic device (most often in the form of an integrated circuit) that measures the passage of time.
Although the term often refers to the devices in personal computers, servers and embedded systems, RTCs are present in almost any electronic device which needs to keep accurate time.
The term real-time clock is used to avoid confusion with ordinary hardware clocks which are only signals that govern digital electronics, and do not count time in human units. RTC should not be confused with real-time computing, which shares its three-letter acronym but does not directly relate to time of day.
Although keeping time can be done without an RTC, using one has benefits such as Low power consumption (important when running from alternate power), frees the main system for time-critical tasks and sometimes more accurate than other methods
A GPS receiver can shorten its startup time by comparing the current time, according to its RTC, with the time at which it last had a valid signal. If it has been less than a few hours, then the previous ephemeris is still usable.
- Provides year, month, day, weekday, hours, minutes and seconds based on 32.768 kHz quartz crystal
- Century flag
- Clock operating voltage: 1.8 V to 5.5 V
- Low backup current; typical 0.25 mA at VDD = 3.0 V and Tamb = 25 °C
- 400 kHz two-wire I2C-bus interface (at VDD = 1.8 V to 5.5 V)
- Programmable clock output for peripheral devices (32.768 kHz, 1024 Hz, 32 Hz and 1 Hz)
- Alarm and timer functions
- Integrated oscillator capacitor
- Internal power-on reset
- I2C-bus slave address: read A3h and write A2h
- Open-drain interrupt pin
- ElectroStatic Discharge (ESD) protection exceeds 2000 V Human Body Model (HBM) per JESD22-A114, 200 V Machine Model (MM) per JESD22-A115 and 2000 V Charged Device Model (CDM) per JESD22-C101
- Latch-up testing is done to JEDEC standard JESD78 which exceeds 100 mA
- Mobile telephones
- Portable instruments
- Electronic metering
- Battery powered products