QT49S-28.63636MAHJ-T

Overview

The QT49S-28.63636MAHJ-T is a surface-mount quartz crystal resonator manufactured by QST, operating at a fundamental frequency of 28.63636 MHz. It utilizes an HC-49/US form factor with SMD mounting capabilities, featuring body dimensions of 12.7 x 4.8 x 3.8 mm. The component exhibits a load capacitance of 18 pF and a maximum equivalent series resistance (ESR) of 30 Ohms. Frequency stability is rated at ±30 ppm across the commercial temperature range (-20°C to +70°C) and ±30 ppm across the extended industrial range (-40°C to +85°C). Resonator tolerance is specified at ±30 ppm.

Feature Summary

• Surface-mount design compatible with automated assembly processes
• HC-49/US package geometry ensuring standardized footprint compatibility
• Wide operational temperature range supporting industrial environmental conditions

Applications

• Automotive body electronics systems
• Industrial control equipment timing circuits
• Medical device clock generation
• Personal electronics oscillator modules

Procurement Notes

Verify the suffix 'HJ' confirms the specific ±30 ppm stability rating for both -20°C to +70°C and -40°C to +85°C ranges. Confirm the 18pF load capacitance matches the target circuit design requirements. Ensure the SMD variant aligns with PCB layout specifications rather than through-hole alternatives.

Selection Notes

Select this component when precise timing is required for automotive or industrial applications demanding wide temperature stability. The 28.63636 MHz frequency is suitable for baud rate generation in communication interfaces. Verify that the 30 Ohm ESR limit is compatible with the oscillator circuit's drive level constraints to prevent frequency pulling or failure.

Part Context

This part belongs to the QT49S series of quartz crystals from QST, which offers various frequency and stability options within the HC-49/US SMD form factor. The series supports diverse electronic applications requiring reliable clock sources. The specific model denotes a high-stability variant designed for environments where standard commercial-grade crystals may not suffice due to thermal variations.

Replacement Considerations

Cross-reference with other manufacturers offering HC-49/US SMD crystals at 28.63636 MHz with ±30 ppm stability and 18pF load capacitance. Ensure mechanical dimensions and pin configuration remain identical to avoid PCB rework. Verify electrical parameters such as ESR and drive level sensitivity match original design specifications.