UM10301
User Manual for NXP Real Time Clocks PCF85x3, PCF85x63,
PCA8565, PCF2123, and PCA21125
Rev. 2.1 — 23 July 2015
User manual
Document information
Info
Content
Keywords
PCF8563, PCF8583, PCF8593, PCA8565, PCF85263, PCF85363,
PCF85063, PCF2123, PCA21125, PCF2120, RTC, real time clock,
timekeeping, crystal, 32.768 kHz, backup.
Abstract
This user manual aims to assist a user of above mentioned Real Time
Clocks in achieving successful design-in and application. It contains
useful hints with respect to electrical schematic and PCB layout as well
as code examples for the well-established NXP PCF8563 and related
Real Time Clocks. Also the more recent Real Time Clocks PCF2123 and
PCA21125 have been taken into account.
NXP Semiconductors
UM10301
User Manual for PCF85x3, PCF85x63, PCA8565, PCF2123, and
PCA21125
UM10301
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2015. All rights reserved.
User manual
Rev. 2.1 — 23 July 2015
2 of 54
Contact information
For more information, please visit:
http://www.nxp.com
Revision history
Rev
Date
Description
2.1
20150723
Fixed readability issue with certain browsers for Fig 9
2
20150717
Second version. Updated section 6.2
01
20081223
Initial version.
This application note / user manual is a complete update of a previous publication titled:
“Application note for the Philips Real Time Clocks PCF8563,73,83,93” which did not have
an official AN/UM number and is superseded by this document.
The contents were revised with lots of additional information added and errors in the
examples corrected. Additionally it includes information with respect to recently introduced
RTCs.