18QHTF21-7.875-PD

Overview

The 18QHTF21-7.875-PD is a standard crystal oscillator (XO) manufactured by Mercury Electronics Ind. Co. Ltd. It operates at a nominal frequency of 7.875 MHz and utilizes LVCMOS output logic levels. The device is designed for operation with a supply voltage of 1.8V. It features a power-down mode capability, allowing the oscillator to be disabled when not in use to conserve energy. 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 interface for digital logic compatibility
• Includes standby or power-down functionality for energy management
• Designed for low-voltage 1.8V operation

Applications

• General-purpose timing reference in embedded systems
• Clock source for microcontrollers requiring 1.8V logic
• Industrial control equipment utilizing standard XO frequencies

Procurement Notes

Verify the specific frequency tolerance and load capacitance requirements against the system design specifications before procurement. Confirm that the 1.8V supply voltage aligns with the target application's power rails. Ensure the 4-SMD no-lead package footprint matches the PCB layout constraints. Cross-reference the manufacturer datasheet for thermal and electrical limits to ensure reliable operation under expected environmental conditions.

Selection Notes

Select this component when a precise 7.875 MHz clock signal is required for 1.8V logic circuits. Consider the power-down feature if system power efficiency is a priority during idle states. Evaluate the package size relative to available board space. Compare stability requirements against other available frequencies within the same series to ensure optimal performance for the specific timing application.

Part Context

This part belongs to the 18QHTF21 series from Mercury Electronics, which offers various standard frequencies in a small surface-mount form factor. The series is characterized by its compatibility with low-voltage digital interfaces and includes options for power management through standby modes. Mercury Electronics specializes in quartz-based timing solutions, providing components for diverse electronic applications requiring stable frequency generation.

Replacement Considerations

Direct substitutes may include other 7.875 MHz LVCMOS oscillators in 4-SMD packages from different manufacturers, provided they support 1.8V operation and similar pin configurations. Verify electrical parameters such as current consumption and startup time before substitution.