MAX3624UTJ2T

Overview

The MAX3624UTJ2T is a low-jitter precision clock generator optimized for networking applications. It integrates a crystal oscillator and a phase-locked loop (PLL) clock multiplier to generate high-frequency outputs for Ethernet, Fibre Channel, SONET/SDH, and other networking applications. The device features ultra-low jitter of 0.36ps RMS and excellent power-supply noise rejection. It provides three LVPECL outputs and one LVCMOS output with selectable dividers. Operating voltage ranges from 3V to 3.6V, with an operating temperature range of 0°C to +85°C in a 32-TQFN package.

Feature Summary

• Ultra-low jitter: 0.14ps RMS (1.875MHz to 20MHz) and 0.36ps RMS (12kHz to 20MHz)
• Integrated crystal oscillator supporting frequencies from 19.375MHz to 27MHz
• Four outputs: Three differential LVPECL (QA, QB0, QB1) and one single-ended LVCMOS (QA_C)
• Excellent power-supply noise rejection without external loop filter capacitor

Applications

• Ethernet Networking Equipment
• Fibre Channel Storage Area Network
• SONET/SDH Network

Procurement Notes

Verify the ordering suffix 'UTJ2T' against official Microchip or Maxim Integrated documentation to confirm specific tape-and-reel packaging and temperature grade details. Ensure compatibility with the 32-TQFN exposed pad thermal requirements during assembly.

Selection Notes

Select this component when designing systems requiring precise clock synthesis for Ethernet, Fibre Channel, or SONET/SDH interfaces. Consider the available output frequencies (e.g., 125MHz, 156.25MHz, 312.5MHz) and the need for LVPECL versus LVCMOS signaling levels. Verify that the input reference source matches the supported crystal or CMOS input specifications.

Part Context

The MAX3624 is part of Maxim Integrated's (now Microchip Technology) portfolio of low-jitter clock generators. It is designed to minimize design risk in network equipment by providing a proprietary PLL architecture with integrated oscillators. The device simplifies board layout by eliminating the need for external loop filter capacitors.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Evaluate alternative clock generators based on matching jitter performance, output types (LVPECL/LVCMOS), and package dimensions if substitution is required.

FAQ

What is the maximum operating frequency for the LVPECL outputs?

The LVPECL outputs (QA, QB0, QB1) are specified up to 320MHz.

Does the MAX3624 require an external loop filter capacitor?

No, the device does not require an external loop filter capacitor.

How is the VCO supply noise filtered?

The VCO supply (VCCA) can be isolated from the core logic using a recommended filter network consisting of a 10.5Ω resistor and decoupling capacitors, provided the power supply is +3.3V ±5%.