QT49S-27.000MAHJ-T

Overview

The QT49S-27.000MAHJ-T is a surface-mount quartz crystal resonator manufactured by QST. It operates at a fundamental frequency of 27 MHz with a load capacitance of 18 pF and an equivalent series resistance of 30 Ohms. The component exhibits a frequency stability of ±30 ppm and a frequency tolerance of ±30 ppm. It is housed in an HC-49/US package with dimensions of 12.7 x 4.8 x 3.8 mm. The device supports an operating temperature range from -40°C to +85°C.

Feature Summary

• Surface-mount construction utilizing the HC-49/US form factor for compact integration
• Designed for stable oscillation at 27 MHz with specified load capacitance
• Operates reliably within industrial temperature ranges

Applications

• Microcontroller clock sources
• Communication module timing references
• Digital signal processing circuits

Procurement Notes

Verify the specific suffix MAHJ-T against official QST documentation to confirm surface-mount configuration and tolerance specifications. Ensure compatibility with reflow soldering profiles for HC-49/US packages. Cross-reference part numbers with authorized distributors to avoid counterfeit components. Confirm that the 18 pF load capacitance matches the target circuit design requirements before procurement.

Selection Notes

Select this component when a 27 MHz surface-mount crystal is required for space-constrained designs. The HC-49/US package offers a balance between performance and footprint compared to larger through-hole variants. Consider the ±30 ppm stability requirement against system timing accuracy needs. Verify that the 30 Ohm ESR aligns with the oscillator circuit's drive level limitations.

Part Context

This part belongs to the QT49S series of quartz crystals from QST. The series includes various frequencies and package types, including both through-hole and surface-mount options. The MAHJ-T suffix typically denotes specific mechanical and electrical characteristics distinct from other series variants like MEEJ.

Replacement Considerations

Direct substitutes must match the 27 MHz frequency, 18 pF load capacitance, and HC-49/US SMD package. Check manufacturer datasheets for equivalent parts with identical ±30 ppm stability and 30 Ohm ESR ratings. Ensure thermal characteristics remain within the -40°C to +85°C range.