QT252S-27.000MEEQ-T

Overview

The QT252S-27.000MEEQ-T is a surface-mount quartz crystal oscillator manufactured by QST, operating at a nominal frequency of 27 MHz. It features a 4-SMD, No Lead package with dimensions of 2.5 mm x 2.0 mm. The component exhibits a frequency stability of ±10 ppm at 25°C and ±10 ppm across the -20°C to 70°C temperature range. It utilizes a load capacitance of 10 pF and has an equivalent series resistance (ESR) of 100 Ohms. The device employs seam seal technology for environmental protection.

Feature Summary

• Seam sealed construction for enhanced environmental durability
• Surface mount design suitable for automated assembly processes
• High frequency stability within specified industrial temperature ranges

Applications

• Clock generation for microcontrollers and digital logic circuits
• RF transmitter and receiver modules requiring stable carrier frequencies
• Communication equipment utilizing 27 MHz band standards

Procurement Notes

Verify the manufacturer designation on official documentation, as this component appears in catalogs from both QST and TXC Corporation due to supply chain relationships. Confirm the specific suffix 'MEEQ' matches the required seam seal and lead-free specifications. Ensure the load capacitance requirement of your circuit aligns with the 10 pF specification to maintain accurate frequency performance. Cross-reference the datasheet version to confirm temperature stability ratings.

Selection Notes

Select this component when a compact 27 MHz reference source is required for space-constrained designs. The 2.5x2.0 mm footprint offers a balance between size and electrical performance compared to larger through-hole alternatives. Consider the ±10 ppm stability sufficient for general-purpose timing applications where higher precision is not critical. Evaluate the 100 Ohm ESR against the oscillator circuit's drive level requirements to prevent over-driving the crystal.

Part Context

This part belongs to the QT252S series of MHz quartz crystals. The series typically includes various frequency options such as 16 MHz and other standard clock rates. These components are designed for general-purpose timing applications in consumer electronics and industrial control systems. The QT252S designation indicates a specific form factor and sealing method distinct from other QST crystal families.

Replacement Considerations

Direct substitutes may include other 27 MHz crystals with identical 2.5x2.0 mm SMD packages and 10 pF load capacitance. Verify that alternative parts meet the same ±10 ppm stability and 100 Ohm ESR specifications. Check compatibility with the PCB land pattern to ensure mechanical fit. Consult manufacturer cross-reference lists for officially approved replacements.