QT49S-14.31818MEEJ-T

Overview

The QT49S-14.31818MEEJ-T is a quartz crystal resonator manufactured by QST, operating at a nominal frequency of 14.31818 MHz. It features a frequency stability and load capacitance tolerance of ±10 ppm. The device utilizes an HC-49/US package with dimensions of 12.7 x 4.8 x 3.8 mm. Key electrical specifications include a load capacitance of 18 pF and an equivalent series resistance (ESR) of 30 Ohms. The unit supports a drive level between 1 and 500 μW, with a typical value of 100 μW. Aging is specified at ±5 ppm maximum during the first year at 25°C. The operational temperature range extends from -20°C to +70°C.

Feature Summary

• Provides precise frequency generation for clocking applications using high-stability quartz technology.
• Designed for reliable operation within standard industrial temperature ranges.
• Utilizes a robust HC-49/US through-hole package for secure mechanical mounting.

Applications

• Microcontroller clock sources
• Communication interface timing circuits
• Digital signal processing systems

Procurement Notes

Verify the specific suffix EEEJ against official QST documentation to confirm pin configuration and termination style. Ensure the selected variant matches the required load capacitance and frequency tolerance for the target circuit design. Cross-reference the datasheet aging specifications and drive level limits to prevent component failure under varying thermal conditions.

Selection Notes

Select this component when a stable 14.31818 MHz reference is required for digital logic or communication protocols. The HC-49/US form factor suits designs prioritizing mechanical durability over compact surface-mount solutions. Evaluate the ±10 ppm stability requirement against system jitter budgets before finalizing the part choice.

Part Context

This model belongs to the QT49S series of quartz crystals from QST. The series offers various frequency options and stability grades, denoted by suffix letters such as E for ±10 ppm stability. The QT49S line is engineered for general-purpose timing applications requiring consistent performance across defined temperature ranges.

Replacement Considerations

Direct substitutes must match the 14.31818 MHz frequency, 18 pF load capacitance, and HC-49/US package. Verify that alternative manufacturers provide equivalent ±10 ppm stability and similar ESR values to maintain circuit timing integrity.