PCF8523U/12AA/1,00

Real Time Clock Overview

The PCF8523U/12AA/1,00 is a bare die CMOS Real-Time Clock (RTC) and calendar optimized for low power consumption. It provides year, month, day, weekday, hours, minutes, and seconds based on a 32.768 kHz quartz crystal with resolution from seconds to years. The device features a 1 MHz Fast-mode Plus (Fm+) I²C interface with read address D1h and write address D0h. It operates at clock voltages between 1.0 V and 5.5 V, with a typical backup current of 150 nA at VDD = 3.0 V and Tamb = 25 °C. Key functional blocks include an offset register for frequency adjustment, selectable integrated oscillator load capacitors (7 pF or 12.5 pF), and a battery switch-over circuit.

Real Time Clock Feature Summary

• CMOS RTC and calendar providing timekeeping based on a 32.768 kHz quartz crystal
• Bidirectional 1 MHz Fast-mode Plus (Fm+) I²C interface
• Battery backup input pin with automatic switch-over circuit upon power failure
• Programmable offset register for fine-tuning clock frequency

Real Time Clock Applications

• Time keeping applications
• Battery powered devices
• Metering

Real Time Clock Procurement Notes

Verify the specific ordering suffix /12AA/1,00 against the manufacturer's official documentation to confirm the delivery form as chips with bumps on a Film Frame Carrier (FFC). Ensure compatibility with bare die handling requirements and wafer mapping specifications before procurement.

Real Time Clock Selection Notes

Select this bare die variant when integrating the RTC directly into custom substrates or system-in-package solutions. Confirm that the design supports the required 12-bump configuration and handles the exposed pad connection to VSS. Verify that the application environment accommodates the operating temperature range and voltage levels specified in the datasheet.

Real Time Clock Part Context

This component is part of the NXP PCF8523 family of real-time clocks. While other variants like PCF8523T (SO8) and PCF8523TK (HVSON8) are available in standard packages, the PCF8523U represents the bare die version intended for advanced packaging integration. It shares the same core functionality and register map as the packaged equivalents.

Real Time Clock Replacement Considerations

Direct replacement requires matching the bare die specification. Packaged versions such as PCF8523T or PCF8523TK cannot be used without redesigning the PCB footprint and interconnects. Ensure the new source provides identical bump hardness and wafer thickness parameters.