SPI-bus Real-Time Clock and calendar | NXP Semiconductors

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SPI-Bus Real-Time Clock and Calendar

PCA21125 Active

The PCA21125 is a CMOS Real-Time Clock (RTC) and calendar optimized for low-power consumption and an operating temperature up to 125 °C. Data is transferred via a Serial Peripheral Interface (SPI-bus) with a maximum data rate of 6.0 Mbit/s. Alarm and timer functions are also available with the possibility to generate a wake-up signal on the interrupt pin.

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Block Diagram

PCA21125 Block Diagram

PCA21125 Block Diagram
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Features

Key Features

  • AEC Q100 compliant for automotive applications
  • Provides year, month, day, weekday, hours, minutes, and seconds based on 32.768 kHz quartz crystal
  • Resolution: seconds to years
  • Clock operating voltage: 1.3 V to 5.5 V
  • Low supply current: typical 0.8 μA at Tamb = 25 °C
  • 4-line SPI-bus with separate, but combinable data input and output
  • Serial interface at VDD = 1.6 V to 5.5 V
  • 1 second or 1 minute interrupt output
  • Freely programmable timer with interrupt capability
  • Freely programmable alarm function with interrupt capability
  • Integrated oscillator capacitor
  • Internal Power-On Reset (POR)
  • Open-drain interrupt pin

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N true 0 PSPPCA21125en 8 Application Note Application Note t789 1 Brochure Brochure t518 1 Data Sheet Data Sheet t520 1 Package Information Package Information t790 1 Packing Information Packing Information t935 1 Selector Guide Selector Guide t528 1 Supporting Information Supporting Information t531 1 User Guide User Guide t792 1 en_US en_US en Data Sheet Data Sheet 1 1 2.0 English 1442053479632700379691 PSP 391.8 KB None None documents None 1442053479632700379691 /docs/en/data-sheet/PCA21125.pdf 391769 /docs/en/data-sheet/PCA21125.pdf PCA21125 documents N N 2014-11-26 SPI-bus Real-Time Clock and calendar /docs/en/data-sheet/PCA21125.pdf /docs/en/data-sheet/PCA21125.pdf Data Sheet N 980000996212993340 2022-12-07 pdf N en Jun 23, 2017 980000996212993340 Data Sheet Y N SPI-bus Real-Time Clock and calendar Application Note Application Note 1 2 1.0 English 1442087330310721534478 PSP 763.2 KB None None documents None 1442087330310721534478 /docs/en/application-note/AN10853.pdf 763238 /docs/en/application-note/AN10853.pdf AN10853 documents N N 2016-07-11 ESD and EMC sensitivity of IC /docs/en/application-note/AN10853.pdf /docs/en/application-note/AN10853.pdf Application Note N 645036621402383989 2025-02-10 pdf N en Mar 14, 2013 645036621402383989 Application Note Y N ESD and EMC sensitivity of IC User Guide User Guide 1 3 2.1 English 1442125649798715943478 PSP 983.6 KB None None documents None 1442125649798715943478 /docs/en/user-guide/UM10301.pdf 983634 /docs/en/user-guide/UM10301.pdf UM10301 documents N N 2016-07-11 User Manual for NXP Real Time Clocks PCF85x3, PCF85x63, PCA8565, PCF2123, and PCA21125 /docs/en/user-guide/UM10301.pdf /docs/en/user-guide/UM10301.pdf User Guide N 132339537837198660 2025-01-10 pdf N en Jul 24, 2015 132339537837198660 User Guide Y N User Manual for NXP Real Time Clocks PCF85x3, PCF85x63, PCA8565, PCF2123, and PCA21125 Brochure Brochure 1 4 2 English NXP provides broad portfolio of lower power and high temperature Real Time Clocks for automotive applications 1442049170618710543515 PSP 354.3 KB None None documents None 1442049170618710543515 /docs/en/brochure/75017665.pdf 354250 /docs/en/brochure/75017665.pdf 75017665 documents N N 2015-07-21 Real-time clocks for automotive applications /docs/en/brochure/75017665.pdf /docs/en/brochure/75017665.pdf Brochure N 712453003803778552 2022-12-07 pdf N en Aug 21, 2019 712453003803778552 Brochure Y N Real-time clocks for automotive applications Package Information Package Information 1 5 1.0 English 1455079139512706823552 PSP 291.5 KB None None documents None 1455079139512706823552 /docs/en/package-information/SOT402-1.pdf 291544 /docs/en/package-information/SOT402-1.pdf SOT402-1 documents N N 2016-10-08 plastic thin shrink small outline package; 14 leads; body width 4.4 mm /docs/en/package-information/SOT402-1.pdf /docs/en/package-information/SOT402-1.pdf Package Information N 302435339416912908 2024-04-12 pdf N en Feb 8, 2016 302435339416912908 Package Information Y N plastic thin shrink small outline package; 14 leads; body width 4.4 mm Packing Information Packing Information 1 6 1.0 English TSSOP14; Reel pack; SMD, 13"Q1/T1 Standard product orientationOrderable part number ending ,118 or JOrdering code (12NC) ending 118 1442131432535729363194 PSP 222.1 KB None None documents None 1442131432535729363194 /docs/en/packing/SOT402-1_118.pdf 222068 /docs/en/packing/SOT402-1_118.pdf SOT402-1_118 documents N N 2013-04-17 TSSOP14; Reel pack; SMD, 13"Q1/T1 Standard product orientationOrderable part number ending ,118 or JOrdering code (12NC) ending 118 /docs/en/packing/SOT402-1_118.pdf /docs/en/packing/SOT402-1_118.pdf Packing Information N 145666923842250347 2024-04-23 pdf N en Apr 8, 2013 145666923842250347 Packing Information Y N TSSOP14; Reel pack; SMD, 13"Q1/T1 Standard product orientationOrderable part number ending ,118 or JOrdering code (12NC) ending 118 Selector Guide Selector Guide 1 7 0 Japanese リアルタイム・クロックセレクターガイド。高精度な計時、長い電池寿命、過酷な環境でのアプリケーションに、NXPの豊富なRTCのポートフォリオからお選びください。 1579625550018748134969ja PSP 1.1 MB None None documents None 1579625550018748134969 /docs/ja/product-selector-guide/RTCSelectorGuideA4.pdf 1111554 /docs/ja/product-selector-guide/RTCSelectorGuideA4.pdf RTCSelectorGuideA4 documents N N 2020-01-21 Real Time Clocks Selector Guide Brochure /docs/ja/product-selector-guide/RTCSelectorGuideA4.pdf /docs/ja/product-selector-guide/RTCSelectorGuideA4.pdf Selector Guide N 553557935274807777 2024-04-12 ja Apr 5, 2023 553557935274807777 Selector Guide Y N リアルタイム・ クロック 5 English Real Time Clocks Selector Guide. For highly accurate time-keeping, long battery life, and rugged environment applications, choose from NXP's extensive portfolio of RTCs. 1579625550018748134969 PSP 1.1 MB None None documents None 1579625550018748134969 /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf 1111554 /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf RTCSelectorGuideA4 documents N N 2020-01-21 Real Time Clocks Selector Guide Brochure /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf Selector Guide N 553557935274807777 2024-04-12 pdf N en Apr 17, 2023 553557935274807777 Selector Guide Y N Real Time Clocks Selector Guide Brochure Supporting Information Supporting Information 1 8 1.0 English SSOP, TSSOP & VSO FOOTPRINT (WAVE SOLDERING) 1442126381432716559822 PSP 16.6 KB None None documents None 1442126381432716559822 /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf 16645 /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf SSOP-TSSOP-VSO-WAVE documents N N 2016-10-08 Footprint for wave soldering /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf Supporting Information N 371282830530968666 2024-10-21 pdf N en Oct 8, 2009 371282830530968666 Supporting Information Y N Footprint for wave soldering false 0 PCA21125 downloads en true 1 Y PSP Y Y Application Note 1 /docs/en/application-note/AN10853.pdf 2016-07-11 1442087330310721534478 PSP 2 Mar 14, 2013 Application Note None /docs/en/application-note/AN10853.pdf English documents 763238 None 645036621402383989 2025-02-10 N /docs/en/application-note/AN10853.pdf ESD and EMC sensitivity of IC /docs/en/application-note/AN10853.pdf documents 645036621402383989 Application Note N en None Y pdf 1.0 N N ESD and EMC sensitivity of IC 763.2 KB AN10853 N 1442087330310721534478 Brochure 1 /docs/en/brochure/75017665.pdf 2015-07-21 1442049170618710543515 PSP 4 Aug 21, 2019 Brochure NXP provides broad portfolio of lower power and high temperature Real Time Clocks for automotive applications None /docs/en/brochure/75017665.pdf English documents 354250 None 712453003803778552 2022-12-07 N /docs/en/brochure/75017665.pdf Real-time clocks for automotive applications /docs/en/brochure/75017665.pdf documents 712453003803778552 Brochure N en None Y pdf 2 N N Real-time clocks for automotive applications 354.3 KB 75017665 N 1442049170618710543515 Data Sheet 1 /docs/en/data-sheet/PCA21125.pdf 2014-11-26 1442053479632700379691 PSP 1 Jun 23, 2017 Data Sheet None /docs/en/data-sheet/PCA21125.pdf English documents 391769 None 980000996212993340 2022-12-07 N /docs/en/data-sheet/PCA21125.pdf SPI-bus Real-Time Clock and calendar /docs/en/data-sheet/PCA21125.pdf documents 980000996212993340 Data Sheet N en None Y pdf 2.0 N N SPI-bus Real-Time Clock and calendar 391.8 KB PCA21125 N 1442053479632700379691 Package Information 1 /docs/en/package-information/SOT402-1.pdf 2016-10-08 1455079139512706823552 PSP 5 Feb 8, 2016 Package Information None /docs/en/package-information/SOT402-1.pdf English documents 291544 None 302435339416912908 2024-04-12 N /docs/en/package-information/SOT402-1.pdf plastic thin shrink small outline package; 14 leads; body width 4.4 mm /docs/en/package-information/SOT402-1.pdf documents 302435339416912908 Package Information N en None Y pdf 1.0 N N plastic thin shrink small outline package; 14 leads; body width 4.4 mm 291.5 KB SOT402-1 N 1455079139512706823552 Packing Information 1 /docs/en/packing/SOT402-1_118.pdf 2013-04-17 1442131432535729363194 PSP 6 Apr 8, 2013 Packing Information TSSOP14; Reel pack; SMD, 13"Q1/T1 Standard product orientationOrderable part number ending ,118 or JOrdering code (12NC) ending 118 None /docs/en/packing/SOT402-1_118.pdf English documents 222068 None 145666923842250347 2024-04-23 N /docs/en/packing/SOT402-1_118.pdf TSSOP14; Reel pack; SMD, 13"Q1/T1 Standard product orientationOrderable part number ending ,118 or JOrdering code (12NC) ending 118 /docs/en/packing/SOT402-1_118.pdf documents 145666923842250347 Packing Information N en None Y pdf 1.0 N N TSSOP14; Reel pack; SMD, 13"Q1/T1 Standard product orientationOrderable part number ending ,118 or JOrdering code (12NC) ending 118 222.1 KB SOT402-1_118 N 1442131432535729363194 Selector Guide 1 /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf 2020-01-21 1579625550018748134969 PSP 7 Apr 17, 2023 Selector Guide Real Time Clocks Selector Guide. For highly accurate time-keeping, long battery life, and rugged environment applications, choose from NXP's extensive portfolio of RTCs. None /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf English documents 1111554 None 553557935274807777 2024-04-12 N /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf Real Time Clocks Selector Guide Brochure /docs/en/product-selector-guide/RTCSelectorGuideA4.pdf documents 553557935274807777 Selector Guide N en None Y pdf 5 N N Real Time Clocks Selector Guide Brochure 1.1 MB RTCSelectorGuideA4 N 1579625550018748134969 Supporting Information 1 /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf 2016-10-08 1442126381432716559822 PSP 8 Oct 8, 2009 Supporting Information SSOP, TSSOP & VSO FOOTPRINT (WAVE SOLDERING) None /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf English documents 16645 None 371282830530968666 2024-10-21 N /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf Footprint for wave soldering /docs/en/supporting-information/SSOP-TSSOP-VSO-WAVE.pdf documents 371282830530968666 Supporting Information N en None Y pdf 1.0 N N Footprint for wave soldering 16.6 KB SSOP-TSSOP-VSO-WAVE N 1442126381432716559822 User Guide 1 /docs/en/user-guide/UM10301.pdf 2016-07-11 1442125649798715943478 PSP 3 Jul 24, 2015 User Guide None /docs/en/user-guide/UM10301.pdf English documents 983634 None 132339537837198660 2025-01-10 N /docs/en/user-guide/UM10301.pdf User Manual for NXP Real Time Clocks PCF85x3, PCF85x63, PCA8565, PCF2123, and PCA21125 /docs/en/user-guide/UM10301.pdf documents 132339537837198660 User Guide N en None Y pdf 2.1 N N User Manual for NXP Real Time Clocks PCF85x3, PCF85x63, PCA8565, PCF2123, and PCA21125 983.6 KB UM10301 N 1442125649798715943478 true Y Products

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