PCA2002DUS/DAZ

Overview

The PCA2002DUS/DA is a CMOS integrated circuit designed for battery-operated wrist watches, utilizing a 32 kHz quartz crystal and a bipolar 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. Typical current consumption is 90 nA. It operates within a supply voltage range of 1.1 V to 3.6 V and supports output periods from 1 s to 30 s with programmable pulse widths between 1 ms and 8 ms.

Feature Summary

• Amplitude-regulated 32 kHz quartz crystal oscillator with integrated capacitance of 5.2 pF
• Electrically programmable time calibration with 1 ppm resolution stored in OTP memory
• Very low current consumption: typically 90 nA between motor pulses
• Programmable output periods (1 s, 5 s, 10 s, 20 s, 30 s) and pulse widths (1 ms to 8 ms)
• Selectable full or chopped (75% duty cycle) motor pulses with optional pulse stretching

Applications

• Driver circuits for bipolar stepping motors in wrist watches
• High immunity motor drive circuits
• Applications requiring high production volumes and accurate time setting

Procurement Notes

Verify the package type is WLCSP8 (SOT1455-1) with dimensions 1.16 mm x 0.86 mm. Confirm the ordering suffix DAZ indicates tape reel dry pack packaging with a minimum order quantity of 4000 units. Ensure the ambient temperature rating matches the -10 °C to +60 °C specification. Check that the marking code on the active side reads PC2002-1.

Selection Notes

Select this component when a low-power watch circuit with programmable output parameters is required. It is suitable for applications where the quartz crystal is the only external component needed. Consider the OTP programming capability for factory calibration of timing accuracy. Ensure the design supports the specific voltage modulation requirements for OTP writing during production.

Part Context

The PCA2002DUS/DA belongs to the PCA200x family of 32 kHz watch circuits. Other variants include wire bond dies like PCA2002U/AB/1. The DUS/DA variant specifically uses a Wafer Level Chip-Size Package (WLCSP). This family is designed for high-volume manufacturing of analog watch movements, offering flexibility in output period and pulse width configuration via OTP memory.

Replacement Considerations

Direct replacements within the same package and functionality include other members of the PCA200x family, such as PCA2000, PCA2001, or PCA2003, provided the OTP type recognition bits are compatible. Verify that any substitute maintains the 8-bump WLCSP footprint and similar electrical characteristics.