QT49-48.000MFEQ-B

Overview

The QT49-48.000MFEQ-B is a through-hole quartz crystal manufactured by QST, operating at a nominal frequency of 48 MHz. It utilizes the HC-49/US package style with dimensions of 11.5 x 5 x 3.68 mm. The component features a load capacitance of 10 pF and an equivalent series resistance (ESR) of 80 Ohms. Frequency stability is specified at ±15 ppm at 25°C and ±10 ppm across the temperature range of -20°C to +70°C.

Feature Summary

• Provides precise timing signals for digital circuits using fundamental mode quartz resonance.
• Designed for through-hole mounting on printed circuit boards via standard lead configuration.
• Maintains stable oscillation frequencies within specified industrial temperature limits.

Applications

• Microcontroller clock sources
• Communication interface timing
• Digital logic circuit synchronization

Procurement Notes

Verify that the target design supports through-hole assembly processes, as this component requires soldering leads rather than surface mount techniques. Confirm that the PCB footprint matches the HC-49/US mechanical outline to ensure proper physical installation. Check that the circuit oscillator design accounts for the 10 pF load capacitance requirement to achieve the specified frequency accuracy. Ensure the operating environment remains within the -20°C to +70°C range to maintain the stated stability specifications.

Selection Notes

Select this part when a reliable, cost-effective timing solution is needed for applications requiring 48 MHz precision. Consider the HC-49/US form factor if space constraints allow for larger components compared to surface-mount alternatives. Evaluate the ±15 ppm stability against system requirements, noting that tighter tolerances may require different series options from the manufacturer. Compare the 80 Ohm ESR with the oscillator circuit's drive level capabilities to prevent over-driving the crystal.

Part Context

This component belongs to the QT49 series of general-purpose quartz crystals produced by QST. The series offers various frequency and tolerance options packaged in the widely used HC-49/US housing. These crystals are commonly found in consumer electronics and industrial equipment where robust, low-cost timing elements are preferred over more complex oscillator modules.

Replacement Considerations

Substitutes must match the 48 MHz frequency, 10 pF load capacitance, and HC-49/US package dimensions. Verify that alternative parts meet or exceed the ±15 ppm stability at 25°C and ±10 ppm over the temperature range. Ensure the replacement has compatible ESR characteristics to maintain circuit oscillation reliability.