18QHTF21-77.500-PD

Overview

The 18QHTF21-77.500-PD is a 77.5 MHz crystal oscillator (XO) manufactured by Mercury Electronics Ind. Co., Ltd. It operates with a supply voltage of 1.8V and features an LVCMOS output interface. The component supports a standby or power-down function for energy management. It is housed in a compact 4-SMD, No Lead package with dimensions of 2.0x1.6 mm. The unit ensures frequency stability of ±50ppm and functions within an operating temperature range of -40°C to 85°C.

Feature Summary

• Supports standby mode for power reduction
• Compact surface-mount footprint
• LVCMOS logic compatibility

Applications

• Portable electronic devices requiring low power consumption
• Communication equipment utilizing standard clock signals
• Embedded systems needing precise timing references

Procurement Notes

Verify the specific frequency tolerance and load capacitance requirements against your circuit design before procurement. Confirm that the 1.8V supply voltage aligns with your system's power rails. Ensure the PCB layout accommodates the 2.0x1.6 mm package size and no-lead soldering profile. Cross-reference the datasheet for any specific handling instructions regarding electrostatic discharge protection during assembly.

Selection Notes

Select this model when a small form factor and low voltage operation are critical constraints. The LVCMOS output simplifies interfacing with digital logic without additional level shifting. Consider the ±50ppm stability if high-precision synchronization is not required. Evaluate the thermal performance within the specified -40°C to 85°C range for your intended environment.

Part Context

This part belongs to the QHTF series of quartz oscillators from Mercury Electronics. The series typically offers various frequencies and voltage options in similar small packages. The 'PD' suffix indicates the inclusion of a power-down feature, distinguishing it from continuous-operation variants. This family targets applications where space and power efficiency are prioritized over ultra-high precision.

Replacement Considerations

Direct substitutes may include other 77.5 MHz LVCMOS oscillators in 2.0x1.6mm packages from different manufacturers. Verify pinout compatibility and electrical specifications such as current consumption and rise/fall times. Ensure the replacement also supports the standby function if power management is required.