PCF8563
APPLICATION CIRCUIT
Method 1: Fixed OSCI capacitor — By evaluating the average capacitance necessary for
the application layout a fixed capacitor can be used. The frequency is best measured via the
32.768 kHz signal available after power-on at the CLKOUT pin. The frequency tolerance
depends on the quartz crystal tolerance, the capacitor tolerance and the device-to-device
tolerance (on average ±5×10 -6 ).
Average deviations of ±5 minutes per year can be easily achieved.
Method 2: OSCI trimmer — The oscillator is tuned to the required accuracy by adjusting a
trimmer capacitor on pin OSCI and measuring the 32.768 kHz signal available after
power-on at the CLKOUT pin.
Method 3: OSCO output — Direct output measurement on pin OSCO (accounting
for test probe capacitance).
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TGS [ Tiger Electronic Co.,Ltd ]
