18QHTF21-12.444444-PD

Overview

The 18QHTF21-12.444444-PD is a standard crystal oscillator manufactured by Mercury Electronics Ind. Co. Ltd. It operates at a fixed frequency of 12.444444 MHz and utilizes LVCMOS output logic. The device is designed for a supply voltage of 1.8V and features a standby or power-down function to manage energy consumption. It is housed in a compact 4-SMD, No Lead package with dimensions of 2.0x1.6 mm. This component serves as a precise clock source for digital circuits requiring low-voltage operation and small form factors.

Feature Summary

• Supports LVCMOS output logic for direct interface with digital systems
• Includes standby and power-down functionality for power management
• Utilizes a leadless SMD package for surface-mount assembly

Applications

• Clock generation for embedded systems
• Timing reference for communication interfaces
• Power-sensitive portable electronic devices

Procurement Notes

Verify the specific frequency tolerance and load capacitance requirements against the target circuit design before procurement. Confirm that the 1.8V supply voltage aligns with the system's power rails. Ensure the PCB footprint matches the 2.0x1.6 mm 4-SMD no-lead package specifications to guarantee proper soldering and mechanical stability during assembly processes.

Selection Notes

Select this model when a precise 12.444444 MHz clock signal is required within a constrained physical space. The choice is appropriate for designs prioritizing low voltage operation at 1.8V and the need for active power management through standby modes. Consider the LVCMOS compatibility with downstream logic families to ensure signal integrity without additional level shifting components.

Part Context

This part belongs to the 18QHTF21 series of standard XO oscillators from Mercury Electronics. The series offers various frequencies while maintaining consistent electrical characteristics and package dimensions. The 'PD' suffix indicates the inclusion of power-down capabilities, distinguishing it from non-power-managed variants within the same product line.

Replacement Considerations

Direct substitutes include other 18QHTF21 series parts with identical pinout and voltage ratings but different frequencies, such as the 18QHTF21-51.200-PD or 18QHTF21-8.000-PD, provided the system timing requirements are adjusted accordingly.