PCF8563TS Philips Semiconductors, PCF8563TS Datasheet - Page 21

• Manufacturer Part Number: PCF8563TS
• Description: Real-time clock/calendar
• Manufacturer: Philips Semiconductors

Philips Semiconductors
12. Application information
9397 750 04855
Product specification
Fig 19. Application diagram.
handbook, full pagewidth
12.1 Quartz crystal frequency adjustment
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
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).
1 F
OSCI
OSCO
CLOCK CALENDAR
PCF8563
V SS
V DD
16 April 1999
SDA
SCL
SDA
(I
2
C-bus)
SCL
SDA
SCL
V DD
R
TRANSMITTER/
R
RECEIVER
MASTER
R: pull-up resistor
R =
C b
V DD
t r
MGM665
Real-time clock/calendar
© Philips Electronics N.V. 1999. All rights reserved.
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PCF8563
6
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