QT49-3.579545MAHE-B

Overview

The QST QT49-3.579545MAHE-B is a fundamental quartz crystal resonator operating at a nominal frequency of 3.579545 MHz. It utilizes an AT-cut design housed in a hermetically sealed HC-49S (HC-49/US) through-hole package with two pins. The component exhibits a frequency tolerance and stability of ±30 ppm, with a load capacitance of 12 pF and a series resistance of 200 Ohms. It supports a fundamental operating mode and functions within a temperature range of -40°C to +85°C.

Feature Summary

• Hermetically sealed construction ensures environmental protection and reliability
• AT-cut fundamental quartz design provides stable oscillation characteristics
• Through-hole mounting configuration compatible with standard PCB layouts

Applications

• Microprocessor clock circuits
• Modem communication interfaces
• Wireless application timing references

Procurement Notes

Verify the specific suffix HE against official QST documentation to confirm the exact load capacitance and package variant, as suffixes often denote critical electrical or mechanical differences. Ensure the procurement source provides valid RoHS compliance certificates matching the part number. Cross-reference the datasheet for the specific series resistance value associated with this model to guarantee circuit compatibility.

Selection Notes

Select this component when a fundamental frequency near 3.58 MHz is required for through-hole assembly. The HC-49S package offers robust physical protection compared to surface mount alternatives. Consider the ±30 ppm tolerance for applications where moderate frequency accuracy suffices. Verify that the 12 pF load capacitance matches the oscillator circuit requirements to ensure proper frequency generation.

Part Context

This part belongs to the HC-49 series of quartz crystals, a widely used standard form factor for general-purpose timing applications. The QT49 designation indicates a specific product line from QST focusing on fundamental mode operation. These components are typically utilized in consumer electronics and industrial equipment requiring reliable, low-cost frequency control solutions.

Replacement Considerations

Compatible substitutes include the QT49-3.579545MAAJ-B, which shares the same frequency and package but may differ in load capacitance specifications. Other HC-49S crystals from different manufacturers can be considered if electrical parameters such as series resistance and stability align with the original design requirements.