PCF2003DUS/DAAZ

Overview

The PCF2003DUS/DAAZ is a CMOS integrated circuit designed for battery-operated wrist watches, utilizing a 32 kHz quartz crystal as the timing element and driving a bipolar 1 Hz stepping motor. It features an amplitude-regulated oscillator with excellent frequency stability and high immunity to leakage currents. The device achieves a timing accuracy of 1 ppm through programmable digital frequency adjustment stored in One Time Programmable (OTP) memory. Key electrical characteristics include a typical supply current of 90 nA during operation and 100 nA in stop mode. The IC operates within a supply voltage range of 1.1 V to 3.6 V and supports five programmable output periods ranging from 1 second to 30 seconds.

Feature Summary

• Amplitude-regulated 32 kHz quartz crystal oscillator with integrated capacitance of 5.2 pF
• Automatic motor pulse adaptation function adjusts drive current based on required torque
• Electrically programmable time calibration with 1 ppm resolution stored in OTP memory
• Reliable step detection circuit with correction sequences for missing steps

Applications

• Driver circuits for bipolar stepping motors
• High immunity motor drive circuits
• Battery operated wrist watches

Procurement Notes

Verify that the ordering suffix /DAZ corresponds to the WLCSP8 package variant supplied in tape and reel format. Confirm the ambient temperature rating matches the application requirements, as the specified range is -10 °C to +60 °C. Ensure handling procedures account for ESD sensitivity and light exposure risks associated with the wafer level chip-size package.

Selection Notes

Select this component when designing low-power watch circuits requiring adaptive motor drive capabilities. The internal integration of the oscillator eliminates external components other than the quartz crystal. Consider the OTP programming constraints, as data storage is permanent once written. Verify compatibility with the specific bipolar stepping motor torque requirements to optimize the programmable duty cycle and driving stages.

Part Context

The PCF2003 belongs to the PCF200x family of watch circuits, which includes variants such as the PCA2000, PCA2001, and PCA2002. These devices share similar functional architectures but may differ in type recognition bits or specific feature sets. The DAAZ suffix indicates a specific packaging and shipping configuration for the WLCSP8 die, distinct from bare die or tray options.

Replacement Considerations

Direct replacements within the same family include the PCA2000, PCA2001, and PCA2002, identifiable via type recognition bits in Word D. Cross-family substitution requires verification of pin compatibility and OTP programming protocols. Ensure any substitute maintains the 32 kHz oscillator interface and bipolar motor drive specifications.