18QHTF21-8.450-PD

Overview

The 18QHTF21-8.450-PD is a standard crystal oscillator manufactured by Mercury Electronics Ind. Co. Ltd. It operates at a fixed frequency of 8.45 MHz and utilizes LVCMOS output logic levels. The device is designed for low-power applications, featuring a supply voltage of 1.8V and an integrated standby or power-down function to minimize energy consumption when inactive. It is housed in a compact 4-SMD, No Lead package, suitable for surface-mount assembly on printed circuit boards.

Feature Summary

• Integrates LVCMOS output interface for digital logic compatibility
• Supports standby mode with power-down functionality for energy efficiency
• Utilizes a leadless SMD package for space-constrained designs

Applications

• Battery-powered portable electronic devices
• General-purpose digital clock signal generation
• Low-power embedded system timing references

Procurement Notes

Verify the specific frequency tolerance and load capacitance requirements against the target application's specifications before procurement. Confirm that the 1.8V supply voltage aligns with the system power architecture. Ensure the 4-SMD no-lead footprint matches the PCB land pattern design to guarantee proper soldering and mechanical stability during operation.

Selection Notes

Select this component when a precise 8.45 MHz reference is required alongside strict power management constraints. The LVCMOS output is appropriate for direct interfacing with standard CMOS logic families without additional buffering. Consider the operating temperature range and initial frequency accuracy if the environment involves significant thermal variations or requires tight synchronization.

Part Context

This part belongs to the Mercury Electronics 18QHTF21 series of surface-mount crystal oscillators. The series typically offers various frequencies within the same physical footprint, allowing for design flexibility. The 'PD' suffix indicates the inclusion of power-down control capabilities, distinguishing it from continuous-operation variants within the same product line.

Replacement Considerations

Direct replacements include other 8.45 MHz LVCMOS oscillators in a 4-SMD no-lead package with 1.8V operation. Verify pinout compatibility and electrical characteristics such as rise/fall times and current consumption. Cross-reference with similar Mercury Electronics models like the 18QHTF21-8.450-OE if output enable features are preferred over power-down.