PCF2123TS/1,112 NXP Semiconductors, PCF2123TS/1,112 Datasheet - Page 30
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PCF2123TS/1,112
Manufacturer Part Number
PCF2123TS/1,112
Description
IC SPI RTC/CALENDAR 14-TSSOP
Manufacturer
NXP Semiconductors
Type
Clock/Calendar/Alarmr
Specifications of PCF2123TS/1,112
Package / Case
14-TSSOP
Time Format
HH:MM:SS (12/24 hr)
Date Format
YY-MM-DD-dd
Interface
SPI, 3-Wire Serial
Voltage - Supply
1.1 V ~ 5.5 V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Function
Clock, Calendar
Supply Voltage (max)
5.5 V
Supply Voltage (min)
1.1 V
Maximum Operating Temperature
+ 85 C
Minimum Operating Temperature
- 40 C
Mounting Style
SMD/SMT
Rtc Bus Interface
Serial
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Memory Size
-
Lead Free Status / RoHS Status
Lead free / RoHS Compliant, Lead free / RoHS Compliant
Other names
935286384112
PCF2123TS/1
PCF2123TS/1
PCF2123TS/1
PCF2123TS/1
NXP Semiconductors
PCF2123
Product data sheet
8.9 Offset register
The PCF2123 incorporates an offset register (address 0Dh) which can be used to
implement several functions, such as:
The offset is made once every two hours in the normal mode, or once every hour in the
course mode. Each LSB will introduce an offset of 2.17 ppm for normal mode and
4.34 ppm for course mode. The values of 2.17 ppm and 4.34 ppm are based on a nominal
32.768 kHz clock. The offset value is coded in two’s complement giving a range of
+63 LSB to 64 LSB.
Table 36.
[1]
The correction is made by adding or subtracting 64 Hz clock correction pulses, thereby
changing the period of a single second.
Table 37.
In normal mode, the correction is triggered once per two hours and then correction pulses
are applied once per minute until the programmed correction values have been
implement.
In course mode, the correction is triggered once per hour and then correction pulses are
applied once per minute up to a maximum of 60 minutes. When correction values greater
than 60 are used, additional correction pulses are made in the 59th minute (see
OFFSET[6:0]
0 1 1 1 1 1 1
0 1 1 1 1 1 0
0 0 0 0 0 1 0
0 0 0 0 0 0 1
0 0 0 0 0 0 0
1 1 1 1 1 1 1
1 1 1 1 1 1 0
1 0 0 0 0 0 1
1 0 0 0 0 0 0
Offset in ppm
2.17
4.34
•
•
•
Ageing adjustment
Temperature compensation
Accuracy tuning
Default mode.
:
:
Register Offset_register
Example of converting the offset in ppm to seconds
All information provided in this document is subject to legal disclaimers.
Seconds per
Day
0.187
0.375
Offset value in
decimal
+63
+62
:
+2
+1
0
1
2
:
63
64
Rev. 4 — 22 December 2010
[1]
Week
1.31
2.62
+136.71
+134.54
+4.34
+2.17
2.17
4.34
:
136.71
138.88
Offset value in ppm
Normal mode
MODE = 0
:
0
Month
5.69
11.4
SPI Real time clock/calendar
Course mode
MODE = 1
+273.42
+269.08
:
+8.68
+4.34
0
4.34
8.68
:
273.42
277.76
PCF2123
© NXP B.V. 2010. All rights reserved.
Year
68.2
136
Table
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38).