XTL721-S999-438

Crystals Overview

The Siward XTL721-S999-438 is a surface-mount tuning fork crystal resonator designed for precision timing applications. It operates at a nominal frequency of 32.768 kHz, which facilitates accurate timekeeping through binary division. The component features a load capacitance of 6 pF and a frequency tolerance of ±20 ppm. It utilizes a two-terminal SMD package with no leads, ensuring compact integration into electronic circuits.

Crystals Feature Summary

• Utilizes quartz piezoelectric effect for stable frequency generation
• Compact surface-mount design suitable for space-constrained PCBs
• High reliability construction for consistent performance

Crystals Applications

• Real-time clock circuits in consumer electronics
• Wearable technology devices
• Smart POS terminals

Crystals Procurement Notes

Verify the specific load capacitance requirement of 6 pF against the target circuit design to ensure oscillation stability. Confirm that the application environment does not exceed the specified temperature range. Ensure proper reflow soldering profiles are used for the leadless SMD package to maintain mechanical integrity and electrical contact.

Crystals Selection Notes

Select this component when a low-power, high-stability 32.768 kHz reference is required for timekeeping functions. The 6 pF load capacitance distinguishes it from other variants like the 12.5 pF models, requiring careful matching with the oscillator circuit's stray capacitance. Consider the small form factor for dense layout designs.

Crystals Part Context

This part belongs to the Siward XTL721 series of tuning fork crystals. These components are engineered for use as clock sources in digital systems where precise second-level timing is critical. The series offers various load capacitance options to accommodate different oscillator IC requirements.

Crystals Replacement Considerations

Compatible substitutes include Siward XTL721-S999-437 (7 pF) and XTL721-S999-439 if load capacitance adjustments are feasible. Other manufacturers' 32.768 kHz SMD crystals may be used provided the load capacitance and drive level specifications are matched.