QT49-3.579545MAAJ-B

Overview

The QST QT49-3.579545MAAJ-B is a fundamental mode quartz crystal resonator operating at 3.579545 MHz. It features a frequency tolerance and stability of ±30 ppm within an operating temperature range of -20°C to +70°C. The component utilizes an HC-49/US through-hole package with dimensions of 11.50mm length, 5.00mm width, and a maximum seated height of 3.68mm. It requires a load capacitance of 18 pF and exhibits a series resistance of 200 Ohms. This device is RoHS compliant and designed for standard surface or board mounting applications requiring precise timing references.

Feature Summary

• Fundamental oscillation mode operation for stable frequency generation
• Through-hole HC-49/US package construction for robust mechanical mounting
• Compliant with RoHS environmental standards for restricted hazardous substances

Applications

• NTSC color subcarrier frequency reference in video processing equipment
• Microcontroller clock source circuits requiring 3.58 MHz timing
• Industrial control systems utilizing through-hole mounting constraints

Procurement Notes

Verify the specific ordering suffix matches the required tolerance and load capacitance specifications. Confirm that the HC-49/US package dimensions align with the target PCB footprint and clearance requirements. Ensure the operating temperature range of -20°C to +70°C meets the environmental conditions of the final assembly. Cross-reference the manufacturer's current product status to confirm availability before finalizing procurement plans.

Selection Notes

Select this component when a fundamental mode crystal at 3.579545 MHz is required for NTSC-compatible applications. The HC-49/US package is suitable for manual soldering or wave soldering processes where through-hole technology is mandated. Consider the ±30 ppm stability requirement against the system's jitter and phase noise budget. Verify that the 18 pF load capacitance matches the oscillator circuit design parameters to ensure accurate frequency output.

Part Context

This part belongs to the QT49 series of quartz crystals manufactured by QST Products LLC. The series offers various frequencies and tolerances within the HC-49/US form factor. These components are widely used in consumer electronics and industrial controls where reliable, low-cost timing solutions are necessary. The specific model addresses the legacy NTSC frequency standard commonly found in analog and mixed-signal signal processing chains.

Replacement Considerations

Direct substitutes include other manufacturers' HC-49/US crystals with identical 3.579545 MHz frequency, 18 pF load capacitance, and ±30 ppm tolerance. Ensure any replacement maintains the same fundamental mode operation and series resistance characteristics. Verify that alternative parts meet the same RoHS compliance and operating temperature range specifications.