QT49S-25.000MAHJ-T

Overview

The QT49S-25.000MAHJ-T is a surface-mount crystal oscillator manufactured by QST, operating at a nominal frequency of 25 MHz. It features a frequency stability and tolerance of ±30 ppm and an equivalent series resistance (ESR) of 30 Ohms. The component utilizes a load capacitance of 18 pF and is housed in the HC-49/US package with dimensions of 12.7 mm x 4.8 mm x 3.8 mm. Designed for SMD/SMT installation, it supports a standard operating temperature range.

Feature Summary

• Surface-mount design compatible with automated assembly processes
• High frequency stability suitable for precision timing applications
• Standardized HC-49/US form factor for broad compatibility

Applications

• Automotive body electronics and lighting systems
• Industrial control equipment
• Medical instrumentation devices
• Personal electronic gadgets

Procurement Notes

Verify the manufacturer designation carefully, as sources list both QST and TXC Corporation for this part number. Confirm the specific package dimensions and ESR values against the official datasheet to ensure compatibility with your circuit design requirements before finalizing procurement decisions.

Selection Notes

Select this component when a 25 MHz reference signal is required with ±30 ppm stability. Ensure the PCB layout accommodates the HC-49/US footprint dimensions of 12.7 mm x 4.8 mm. Verify that the system load capacitance matches the specified 18 pF requirement to maintain accurate frequency performance.

Part Context

This model belongs to the QT49S series of quartz crystals from QST. It serves as a fundamental timing element for digital circuits requiring stable clock signals. The HC-49/US package provides a robust mechanical structure while maintaining a compact profile suitable for modern electronic assemblies.

Replacement Considerations

Cross-reference with other 25 MHz HC-49/US crystals offering ±30 ppm stability and 18 pF load capacitance. Ensure substitute components match the physical dimensions and electrical characteristics, specifically the 30 Ohm ESR, to guarantee seamless integration.