PCA85073ADP/Q900Z

Real Time Clock Overview

The PCA85073ADP/Q900Z is an automotive-grade CMOS real-time clock and calendar compliant with AEC-Q100 Grade 2. It operates on a two-line bidirectional I2C-bus with a maximum data rate of 400 kbit/s. The device provides year, month, day, weekday, hours, minutes, and seconds based on a 32.768 kHz quartz crystal. It features low current consumption, typically 0.25 μA at VDD = 3.0 V and Tamb = 25 °C. The clock operating voltage ranges from 0.9 V to 5.5 V, supporting high-temperature operation from -40 °C to +105 °C.

Real Time Clock Feature Summary

• AEC-Q100 Grade 2 compliant for automotive applications
• Programmable clock output (CLKOUT) providing frequencies from 32.768 kHz down to 1 Hz
• Internal offset register allows fine-tuning of the clock frequency with ±2 ppm accuracy
• Alarm function with minute and half-minute interrupt capabilities

Real Time Clock Applications

• Dashboard timing
• Infotainment unit synchronization
• Telematics systems
• Body control and battery management

Real Time Clock Procurement Notes

Verify that the package type matches TSSOP8 (SOT505-1). Confirm the ordering suffix Q900 indicates the Reel packing method in a Static Shielding Bag. Ensure the temperature range requirement aligns with the specified -40 °C to +105 °C operational limit.

Real Time Clock Selection Notes

Select this component for automotive environments requiring AEC-Q100 Grade 2 qualification. Use the internal oscillator load capacitor selection (7 pF or 12.5 pF) to match the external quartz crystal specifications. Consider the offset register for precision timekeeping adjustments if higher accuracy than standard crystals provides.

Real Time Clock Part Context

The PCA85073ADP/Q900Z serves as a drop-in replacement for the PCA85063ATT/A. The leadframe construction is rougher to provide higher resistance to package delamination. It belongs to NXP's family of tiny RTCs optimized for low power consumption in automotive body electronics.

Real Time Clock Replacement Considerations

This part is explicitly documented as a drop-in replacement for PCA85063ATT/A.