HC-49/U-S4000000AHKB

Crystals Overview

The HC-49/U-S4000000AHKB is an AT-cut crystal oscillator manufactured by Citizen Finedevice Co Ltd. It operates at a nominal frequency of 4 MHz with a load capacitance of 20 pF. The component features a frequency tolerance of ±30 ppm and a frequency stability of 50 ppm. It utilizes a HC-49/US package with radial through-hole mounting. Key electrical parameters include an equivalent series resistance (ESR) of 150 ohms and a maximum drive level of 100 uW. The unit supports an operating temperature range from -10°C to +60°C.

Crystals Feature Summary

• AT-cut resonator technology for stable oscillation
• Radial leaded construction for through-hole integration
• Defined load capacitance matching standard circuit requirements

Crystals Applications

• Microcontroller clock sources
• Communication interface timing
• General-purpose electronic instrumentation

Crystals Procurement Notes

Verify the specific suffix AHKB against official Citizen Finedevice documentation to confirm the 20 pF load capacitance specification, as variations exist within the HC-49/U family. Ensure the application circuit matches the 150 ohm ESR and 100 uW drive level limits. Confirm RoHS compliance status via the manufacturer's current datasheet before finalizing procurement orders.

Crystals Selection Notes

Select this component when a 4 MHz fundamental frequency is required for through-hole PCB designs. The HC-49/US form factor provides mechanical robustness compared to surface-mount alternatives. Engineers must ensure the host circuit impedance aligns with the 20 pF load capacitance to maintain the specified ±30 ppm frequency tolerance across the operational temperature range.

Crystals Part Context

This part belongs to the HC-49/U series of piezoelectric crystals. The series is widely used in consumer electronics and industrial controls. Citizen Finedevice produces these components using precision quartz cutting techniques. The HC-49/U designation refers to the specific metal can housing dimensions and lead configuration standardized for general-purpose timing applications.

Crystals Replacement Considerations

Public confirmed substitute part numbers are not available in the provided source material.