QT252S-40.000MAAV-T

Overview

The QT252S-40.000MAAV-T is a surface-mount quartz crystal oscillator manufactured by QST, designed for precise frequency generation in electronic circuits. It operates at a nominal frequency of 40 MHz with a load capacitance of 8 pF and an equivalent series resistance (ESR) of 60 Ohms. The component exhibits a frequency stability of ±30 ppm at 25°C and maintains this stability across an operating temperature range of -20°C to +70°C. Housed in a compact 2.5x2.0 mm package with four solder pads, it supports reliable integration into space-constrained designs requiring stable clock signals.

Feature Summary

• Provides stable 40 MHz oscillation with ±30 ppm frequency tolerance
• Compact 2.5x2.0 mm surface-mount footprint for space-efficient layouts
• Operates reliably within a -20°C to +70°C temperature range
• Features low ESR of 60 Ohms for efficient circuit driving

Applications

• Clock signal generation for microcontrollers and digital processors
• Timing reference for communication interfaces such as UART or SPI
• Frequency control in consumer electronics and IoT devices
• Oscillator circuits in portable battery-powered equipment

Procurement Notes

Verify the manufacturer part number QT252S-40.000MAAV-T against official QST documentation to ensure authenticity. Confirm that the specified load capacitance (8pF), frequency stability (±30ppm), and temperature range (-20°C to +70°C) match your design requirements. Check for RoHS compliance status if environmental regulations apply to your production process. Ensure compatibility with your PCB reflow profile specifications.

Selection Notes

Select this component when a 40 MHz reference is required in a small SMD package. The 8pF load capacitance must align with the oscillator circuit design to achieve accurate frequency output. Consider the ±30 ppm stability sufficient for most digital timing applications. Evaluate the -20°C to +70°C range against your operational environment. The 60 Ohm ESR should be compatible with the driving gate's output impedance.

Part Context

This crystal belongs to the QT252S series from QST, which offers various frequencies in a standardized 2.5x2.0 mm surface-mount package. The series is commonly used in applications requiring reliable timing sources where board space is limited. Similar parts in the series may differ in frequency, load capacitance, or temperature range, but share the same physical dimensions and mounting style.

Replacement Considerations

Direct substitutes include other 40 MHz crystals in 2.5x2.0 mm packages with matching 8pF load capacitance and ±30 ppm stability. Verify pinout compatibility and electrical parameters before substitution. Cross-reference with QST's official replacement guide or distributor cross-reference tools for validated alternatives.