18QHTF21-7.864-PD

Overview

The 18QHTF21-7.864-PD is a quartz crystal oscillator manufactured by Mercury Electronics Ind. Co. Ltd. It operates at a fundamental frequency of 7.864 MHz with a stability of 50 ppm. The device utilizes an LVCMOS output logic and requires a supply voltage of 1.8V, with a maximum current consumption of 21 mA. It is housed in a compact 2.0x1.6 mm surface-mount package designed for power-down functionality.

Feature Summary

• Integrates a quartz crystal base resonator for stable frequency generation
• Supports low-voltage operation at 1.8V with minimal current draw
• Features a compact 2.0x1.6 mm SMD footprint for space-constrained designs
• Includes power-down capability to reduce energy consumption during standby

Applications

• Portable electronic devices requiring precise clock signals
• Embedded systems with limited power budgets
• Communication modules needing stable frequency references
• Consumer electronics utilizing LVCMOS interfaces

Procurement Notes

Verify the specific frequency tolerance and load capacitance requirements against your circuit design before ordering. Confirm that the 1.8V supply rail can maintain stable voltage under peak current conditions of 21 mA. Ensure the PCB layout accommodates the 2.0x1.6 mm package dimensions and thermal requirements for reliable long-term operation.

Selection Notes

Select this component when a small form factor and low power consumption are critical. The 50 ppm stability suits applications where moderate frequency accuracy is acceptable. Consider the LVCMOS output compatibility with your microcontroller or FPGA inputs. Evaluate if the power-down feature aligns with your system's sleep mode strategies to maximize battery life.

Part Context

This part belongs to Mercury Electronics' series of surface-mount oscillators. The '18QHTF21' prefix indicates a specific family of quartz-based oscillators optimized for low voltage and small size. The '-PD' suffix denotes the inclusion of a power-down control function, distinguishing it from standard continuous-operation variants within the same physical package.

Replacement Considerations

Direct substitutes must match the 7.864 MHz frequency, 1.8V supply, and 2.0x1.6 mm package. Verify equivalent LVCMOS output characteristics and 50 ppm stability. Check for compatible power-down pin configurations if active standby modes are utilized in the target design.