QT49S-25.000MEEJ-T

Overview

The QT49S-25.000MEEJ-T is a surface-mount quartz crystal oscillator manufactured by QST, designed for precise timing applications. It operates at a nominal frequency of 25 MHz with a frequency tolerance of ±10 ppm at 25°C and a stability of ±10 ppm over the temperature range of -20°C to +70°C. The component features an HC-49/US package form factor with physical dimensions of 12.7 x 4.8 x 3.8 mm. It utilizes a load capacitance of 18 pF and exhibits an equivalent series resistance (ESR) of 30 Ohms. The device is RoHS compliant and lead-free, ensuring environmental safety standards are met for modern electronic assemblies.

Feature Summary

• Surface mount construction in HC-49/US package
• High frequency stability across wide temperature ranges
• RoHS compliant and lead-free manufacturing

Applications

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

Procurement Notes

Verify the specific ordering suffix against official QST documentation to ensure correct frequency tolerance and stability specifications. Confirm that the HC-49/US surface mount footprint matches the target PCB design. Check for RoHS compliance status if required by project regulations. Ensure the load capacitance requirement aligns with the host circuit's design parameters before finalizing procurement.

Selection Notes

Select this component when a 25 MHz reference is required with tight ±10 ppm tolerance. The HC-49/US SMD package offers a balance of performance and board space efficiency compared to through-hole alternatives. Consider the operating temperature range of -20°C to +70°C for environmental suitability. Verify compatibility with the system's load capacitance requirements to maintain accurate frequency output.

Part Context

The QT49S series represents QST's line of surface-mount quartz crystals. This specific model integrates standard crystal functionality into a compact form factor suitable for automated assembly processes. It serves as a fundamental timing element in various electronic systems requiring stable oscillation frequencies.

Replacement Considerations

Direct substitutes must match the 25 MHz frequency, 18 pF load capacitance, and HC-49/US SMD package. Verify equivalent electrical characteristics including ESR and stability ratings. Cross-reference manufacturer datasheets to confirm pinout and mechanical compatibility.