18QHTF21-11.945-PD

Overview

The 18QHTF21-11.945-PD is a standard crystal oscillator (XO) manufactured by Mercury Electronics Ind. Co. Ltd. It operates at a fixed frequency of 11.945 MHz and utilizes LVCMOS output logic levels. The device is designed for low-power applications, featuring a supply voltage of 1.8V and supporting a standby or power-down mode to reduce energy consumption during inactive periods. The component is housed in a compact 4-SMD, no-lead package, suitable for surface-mount assembly on printed circuit boards.

Feature Summary

• Supports LVCMOS output logic for digital interface compatibility
• Includes standby functionality for power management
• Utilizes a leadless SMD package for space-efficient mounting

Applications

• Digital signal processing systems requiring precise clock references
• Communication equipment utilizing standard frequency protocols
• Embedded control units with low-voltage power constraints

Procurement Notes

Verify the specific frequency tolerance and load capacitance requirements against the target circuit design before procurement. Confirm that the 1.8V supply rail is stable within the operational limits specified in the official datasheet. Ensure the PCB footprint matches the 4-SMD no-lead package dimensions to prevent assembly errors. Cross-reference the part number suffix to confirm the exact variant specifications.

Selection Notes

Select this component when a fixed 11.945 MHz reference is required for LVCMOS-compatible digital circuits. Consider the 1.8V operating voltage as a primary constraint for power supply design. The standby feature makes it suitable for battery-operated or energy-sensitive devices. Evaluate the thermal performance and package size relative to the available board space and surrounding components.

Part Context

This oscillator belongs to the 18QHTF21 series from Mercury Electronics, which offers various frequencies within a standardized 1.8V LVCMOS format. The series is characterized by its small form factor and low power consumption, targeting modern portable electronics. The 'PD' suffix typically indicates specific packaging or testing configurations defined by the manufacturer.

Replacement Considerations

Direct substitutes include other 11.945 MHz LVCMOS oscillators in 4-SMD packages from manufacturers such as Epson, NDK, or SiTime. Ensure replacement parts match the 1.8V supply requirement and pinout configuration. Verify that alternative sources offer comparable frequency stability and phase noise specifications.