PCF2123

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The PCF2123 is a CMOS Real-Time Clock (RTC) and calendar optimized for low power applications. Data is transferred serially via a Serial Peripheral Interface (SPI-bus) with a maximum data rate of 6.25 Mbit/s. An alarm and timer function is also available providing the possibility to generate a wake-up signal on an interrupt pin. An offset register allows fine tuning of the clock.

Data Sheet

Application Notes

Product Details

Block Diagram

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PCF2123
PCF2123TS, PCF2123U

PCF2123

PCF2123TS, PCF2123U

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Features

Key Features

Real time clock provides year, month, day, weekday, hours, minutes, and seconds based on a 32.768 kHz quartz crystal
Low backup current while running: typical 100 nA at V_DD = 2.0 V and T_amb = 25 ℃
Resolution: seconds to years
Watchdog functionality
Freely programmable timer and alarm with interrupt capability
Clock operating voltage: 1.1 V to 5.5 V
3 line SPI-bus with separate, but combinable data input and output
Serial interface at V_DD = 1.8 V to 5.5 V
1 second or 1 minute interrupt output
Integrated oscillator load capacitors for C_L = 7 pF
Internal Power-On Reset (POR)
Open-drain interrupt and clock output pins
Programmable offset register for frequency adjustment

Product Programs

Product Longevity

Participating products are available for a minimum of 10 years. Designated participating products developed for the automotive, telecom and medical segments are available for a minimum of 15 years.

Buy/Parametrics

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Documentation

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1-5 of 12 documents

Data Sheet
SPI Real time clock/calendar

PDFRev 6.0Jul 15, 2013821.0 KBPCF2123English
Application Note
Improved timekeeping accuracy with PCF85063, PCF8523 and PCF2123 using an external temperature sensor

PDFRev 1.0Mar 6, 2015316.8 KBAN11247English
Application Note
ESD and EMC sensitivity of IC

PDFRev 1.0Mar 14, 2013763.2 KBAN10853English
Application Note
Handling bare die

PDFRev 2.0Jun 16, 20111.7 MBAN10706English
User Guide
Demo Board OM13512 for the SPI-Bus RTC PCF2123

PDFRev 1.0Oct 5, 2015400.7 KBUM10759English
User Guide
User Manual for NXP Real Time Clocks PCF85x3, PCF85x63, PCA8565, PCF2123, and PCA21125

PDFRev 2.1Jul 24, 2015983.6 KBUM10301English
Brochure
NXP ultra-low-power RTC/calendars PCF8523 and PCF2123

PDFRev 1.0Aug 21, 2019289.3 KB75017076English
Package Information
SOT758-1

PDFRev 2Jun 18, 2024135.8 KBSOT758-1English
Package Information
plastic thin shrink small outline package; 14 leads; body width 4.4 mm

PDFRev 1.0Feb 8, 2016291.5 KBSOT402-1English
Packing Information
HVQFN16; Reel Pack; SMD, 13"Q1/T1 Standard Product Orientation Orderable Part Number Ending ,118 or JOrdering Code (12NC) Ending 118

PDFRev 2.0Apr 18, 2013267.8 KBSOT758-1_118English
Packing Information
TSSOP14; Reel pack; SMD, 13"Q1/T1 Standard product orientationOrderable part number ending ,118 or JOrdering code (12NC) ending 118

PDFRev 1.0Apr 8, 2013222.1 KBSOT402-1_118English
Selector Guide
Real Time Clocks Selector Guide Brochure

PDFRev 5Apr 17, 20231.1 MBRTCSelectorGuideA4English, 日本語

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Design Resources

Design Files

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2 design files

Receive the full breakdown. See the product footprint and more in the eCad file.

Symbols and Footprints
PCF2123BS-1-HVQFN16-CAD Symbol and PCB Footprint – BXL File

ZIPRev 1Sep 22, 2020 11:16:0051.1 KBPCF2123BS-1-HVQFN16-BXL
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Symbols and Footprints
PCF2123BS_1-HVQFN16-CAD Symbol and PCB Footprint – BXL File

ZIPRev 1Jul 9, 2020 14:03:0051.1 KBPCF2123BS_1-HVQFN16-BXL
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Hardware

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2 hardware offerings

Complete Solution
NXP Rapid IoT Prototyping Kit

IOT-PROTOTYPING
Evaluation and Development Boards
Demo Board for the SPI-Bus RTC PCF2123

OM13512

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SPI Real-Time Clock/Calendar