QT49-20.500MAHQ-B

Overview

The QT49-20.500MAHQ-B is a fundamental-mode quartz crystal resonator manufactured by QST, designed for precise frequency generation in electronic circuits. Operating at a nominal frequency of 20.5 MHz, this component utilizes the HC-49S through-hole package configuration. It features a load capacitance of 10 pF and maintains a frequency stability of ±30 ppm across the full operating temperature range of -40°C to +85°C. The device exhibits a tolerance of ±30 ppm at 25°C. This crystal is engineered for reliable performance in applications requiring stable clock signals or reference frequencies within standard industrial temperature limits.

Feature Summary

• Fundamental mode operation ensures accurate frequency generation without overtone complications.
• HC-49S through-hole package provides robust mechanical mounting and compatibility with standard PCB layouts.
• Wide temperature stability maintains consistent performance from -40°C to +85°C.
• Low load capacitance requirement facilitates efficient circuit design with minimal external components.

Applications

• Microcontroller clock source generation
• Communication interface timing references
• Industrial control system oscillators
• Consumer electronics timing circuits

Procurement Notes

Verify that the specific ordering suffix matches the required load capacitance and stability specifications. Confirm the package type corresponds to the intended PCB footprint. Ensure the manufacturer designation aligns with quality requirements. Cross-reference the date code for freshness if long-term storage is anticipated. Validate RoHS compliance status against current regulatory standards for the target market.

Selection Notes

Select this component when a fundamental-mode crystal is required for 20.5 MHz applications. Consider the HC-49S package size constraints during layout planning. Evaluate the ±30 ppm stability against system timing budget requirements. Compare load capacitance needs with oscillator circuit design parameters. Assess thermal environment suitability for the specified -40°C to +85°C range.

Part Context

This part belongs to the QT49 series of quartz crystals from QST, which offers various frequencies and packages. The HC-49S variant is a widely used through-hole format known for durability. Similar parts in the series may differ in frequency, package style, or electrical characteristics. The series supports diverse applications requiring stable frequency references. Designers often choose this series for cost-effective and reliable timing solutions.

Replacement Considerations

Direct substitutes must match the 20.5 MHz frequency, HC-49S package, 10 pF load capacitance, and ±30 ppm stability. Verify equivalent electrical parameters before substitution. Check pin compatibility and mechanical dimensions. Ensure thermal performance meets application requirements. Consult manufacturer cross-reference guides for approved alternatives.