UM10766
User manual for the I2C-bus RTC PCF85263A demo board
OM13510
Rev. 3 — 2 May 2016
User manual
Document information
Info
Content
Keywords
Abstract
PCF85263, OM13510, demo board, how to get started, I
2
C-bus, RTC,
Real-Time Clock, tuning, time stamp, battery switch, elapsed time counter
User manual for the RTC I
2
C-bus demo board OM13510 which contains
the PCF85263A
NXP Semiconductors
UM10766
User manual for the I2C-bus RTC PCF85263A demo board OM13510
Revision history
Rev
Date
v.3
v.2
v.1
20160502
20151103
20131115
Description
Fig 4:
Corrected ID mark
Revised user manual
new user manual, first revision
Contact information
For more information, please visit:
http://www.nxp.com
For sales office addresses, please send an email to:
salesaddresses@nxp.com
UM10766
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2016. All rights reserved.
User manual
Rev. 3 — 2 May 2016
2 of 14
NXP Semiconductors
UM10766
User manual for the I2C-bus RTC PCF85263A demo board OM13510
1. Introduction
The PCF85263A is part of the PCF85x63 family of CMOS Real-Time Clocks (RTCs
optimized for low power consumption). Different features sets are available.
The OM13510 is the ideal evaluation and demo board to be used in the design phase of
any project; just power and I
2
C-bus must be connected.
A separate dedicated demo board and a user manual is available for the I
2
C-bus RTCs
PCF85063ATL and PCF85063TP: OM11059A and UM10698
2. Key features
2.1 Demo board OM13510
The RTC PCF85263ATL with I
2
C-bus is mounted together with a quartz crystal, a lithium
battery plus the blocking capacitor, buffering the supply voltage. A push button allows
activating the time stamp. All signals are accessible on a line of pins, overcoming the
difficulties to contact the tiny package directly.
2.2 Real time clock PCF85263A
•
Very small form factor: leadless package (DFN2626-10 for PCF85263ATL) just
2.6
×
2.6
×
0.5 mm, SO8, TSSOP8 and TSSOP10 packages will be released too.
•
Counting: 100
th
seconds, seconds, minutes, hours, days, week days, month and
years
•
Three timestamp register sets
•
Battery back-up circuit, accepting battery voltage larger or smaller than V
DD
•
The oscillator is based on a 32.768 kHz quartz crystal
•
Stop-watch mode for elapsed time counting. From 0 to 999’999 hours with a
resolution of 1/100 second.
•
Two independent alarms
•
WatchDog timer
•
Two independent interrupt generators/outputs
•
Generates an interrupt automatically every second or every minute, independent of
alarm facility
•
Programmable offset register for frequency adjustment to compensate quartz
tolerance
UM10766
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2016. All rights reserved.
User manual
Rev. 3 — 2 May 2016
3 of 14
NXP Semiconductors
UM10766
User manual for the I2C-bus RTC PCF85263A demo board OM13510
Fig 1.
Block diagram of PCF85263A
3. Hardware set-up
3.1 General requirement for the RTC PCF85263A
The RTC circuit just requires one external part: tuning fork quartz as resonator. The
oscillation capacitors are integrated and therefore there is no need for external
capacitors. The quartz crystal must be placed close to the RTC circuit, avoiding long
lines which may pick up noise. Avoid any tracks with high frequency signals (fast edges)
close to the RTC, quartz, or quartz interconnect.
The I
2
C-bus interface works up to 400 kHz. Supply voltage: 1.8 V to 5.5 V. The RTC,
excluding the I
2
C-bus interface, is however operating down to a lower voltage. It is
recommended to have a decoupling capacitor of 100 nF on the V
DD
-V
SS
rails close by.
Due to the low power consumption of below 1 μW, no precautions for heat dissipations
are required, even in sealed housing environment.
Frequencies of 1 Hz to 32.768 kHz at CLKOUT can be used to measure the frequency
for calibration and/or be used for general purpose e.g. as reference for frequency
generation with a PLL.
UM10766
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2016. All rights reserved.
User manual
Rev. 3 — 2 May 2016
4 of 14
NXP Semiconductors
UM10766
User manual for the I2C-bus RTC PCF85263A demo board OM13510
Fig 2.
Interfacing to the microcontroller
3.2 Demo boards for OM13510
Universal
connector P2
Top side
Time stamp
Switch
J6
Back up
battery
P1 option to
connect to
OM13320
Bottom side
Quartz
RTC
Fig 3.
PCF13263 Demo board OM13510 (original version)
UM10766
All information provided in this document is subject to legal disclaimers.
© NXP B.V. 2016. All rights reserved.
User manual
Rev. 3 — 2 May 2016
5 of 14