MAX9450EHJ+

Overview

The MAX9450EHJ+ is a high-precision clock generator with an integrated Voltage-Controlled Crystal Oscillator (VCXO), designed for SONET/SDH, Gigabit Ethernet, and 3G base station applications. It accepts differential inputs in LVPECL, LVDS, or LVCMOS formats within an 8kHz to 500MHz range. The device provides two differential outputs configured as LVPECL, operating up to 160MHz. Key electrical parameters include a supply voltage of 2.4V to 3.6V, period jitter less than 0.8ps RMS (12kHz–20MHz band), and phase noise attenuation greater than -130dBc/Hz at 100kHz. It features hitless input switching and internal holdover capability.

Feature Summary

• Integrated VCXO eliminates external components for cost-effective high-precision clock generation
• Dual differential inputs support LVPECL, LVDS, and LVCMOS signals from 8kHz to 500MHz
• Hitless input clock monitor allows seamless switching between reference sources upon failure
• Internal holdover function maintains frequency within ±20ppm during total input loss

Applications

• SONET/SDH systems timing
• 10 Gigabit Network Routers and Switches
• 3G Cellular Phone Base Stations
• General Jitter Attenuation

Procurement Notes

Verify the EHJ suffix indicates the standard plastic TQFP package with exposed paddle. Confirm RoHS compliance status (+) against specific distributor listings, as lead-free availability may vary by production lot. Check current lifecycle status, as this component family has faced discontinuation notices in some regions.

Selection Notes

Select the MAX9450 variant specifically for LVPECL output requirements; other variants in the series provide HSTL or LVDS outputs. Ensure the application requires the integrated VCXO feature to justify selection over standard clock generators. Verify that the required output frequency falls within the 15MHz to 160MHz operational range defined by the crystal selection.

Part Context

This component belongs to the MAX9450/MAX9451/MAX9452 family of high-precision clock generators manufactured originally by Maxim Integrated, now part of Analog Devices. The MAX9450 specifically denotes the LVPECL output configuration, distinguishing it from the MAX9451 (HSTL) and MAX9452 (LVDS). All three share identical pinouts and core functionality.

Replacement Considerations

Publicly confirmed direct substitute part numbers are not available in the provided documentation. Cross-referencing with MAX9451EHJ+ or MAX9452EHJ+ is possible only if the output signaling format (HSTL/LVDS vs LVPECL) matches the design requirements.