PCA8565 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 4 — 5 December 2014 34 of 48
NXP Semiconductors
PCA8565
Real time clock/calendar
15.1 Quartz frequency adjustment
15.1.1 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 pin CLKOUT. The frequency tolerance depends on the quartz
crystal tolerance, the capacitor tolerance and the device-to-device tolerance (on average
). Average deviations of 5 minutes per year can be easily achieved.
15.1.2 Method 2: OSCI trimmer
Using the 32.768 kHz signal available after power-on at pin CLKOUT, fast setting of a
trimmer is possible.
15.1.3 Method 3: OSCO output
Direct measurement of OSCO out (allowing for test probe capacitance).
16. Test information
16.1 Quality information
This product has been qualified in accordance with the Automotive Electronics Council
(AEC) standard Q100 - Failure mechanism based stress test qualification for integrated
circuits, and is suitable for use in automotive applications.
