PCF8564ACX9/B/1,02

Real Time Clock Overview

The PCF8564ACX9/B/1,02 is a CMOS real-time clock 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. The device features a wide clock operating voltage of 1.0 V to 5.5 V with a typical backup current of 250 nA at 3.0 V and 25 °C. Communication occurs via a 400 kHz two-wire I²C interface (1.8 V to 5.5 V). Additional functions include a programmable clock output, interrupt output, alarm and timer capabilities, a low-voltage detector, and an internal Power-On Reset.

Real Time Clock Feature Summary

• Provides timekeeping based on a 32.768 kHz quartz crystal with BCD-coded registers.
• Operates with a wide clock voltage range of 1.0 V to 5.5 V and low backup current of 250 nA typical.
• Features a 400 kHz I²C interface with slave addresses A3h (read) and A2h (write).
• Includes programmable clock outputs (32.768 kHz, 1.024 kHz, 32 Hz, 1 Hz), alarms, timers, and a low-voltage detector.

Real Time Clock Applications

• Timing devices including time-of-day tracking and process timing.
• Portable instruments requiring precise timekeeping.
• Electronic metering systems.
• Battery-powered products utilizing low standby currents.

Real Time Clock Procurement Notes

Verify the specific ordering suffix against the manufacturer's documentation to confirm package type and delivery form. The provided model indicates a bare die configuration; ensure compatibility with assembly processes for wire bond or bump die variants. Cross-reference the sales item number to confirm availability and revision status before procurement.

Real Time Clock Selection Notes

Select this component when a low-power RTC with integrated oscillator capacitors is required. Ensure the system voltage supports the 1.0 V to 5.5 V operating range. Verify that the I²C bus speed does not exceed 400 kbit/s. Consider the need for external interrupts if utilizing the alarm or timer flags, as the INT pin requires appropriate pull-up configurations.

Real Time Clock Part Context

The PCF8564A series serves as a low-power real-time clock solution within NXP's portfolio. It shares functional similarities with the PCF8563 but includes additional features such as a low-voltage detector and specific test modes. The ACX9 variant denotes a specific packaging or substrate configuration distinct from standard SO8 or TSSOP packages found in other revisions.

Real Time Clock Replacement Considerations

PCF8563: Functionally similar RTC with comparable I²C interface and register map, though lacking the low-voltage detector present in the PCF8564A.