85311AMILFT

Overview

The 85311AMILFT is a low skew, dual 1-to-5 differential-to-2.5V/3.3V ECL/LVPECL fanout buffer manufactured by Renesas Electronics Corporation. It features two differential clock input pairs (CLKx, nCLKx) capable of accepting LVDS, LVPECL, LVHSTL, SSTL, and HCSL signals. The device translates single-ended inputs to 3.3V LVPECL levels with resistor bias on the nCLKx input. Key electrical parameters include a maximum output frequency of 700MHz, typical output skew of 25ps, part-to-part skew of 270ps, propagation delay of 1.7ns, and additive phase jitter RMS of less than 0.13ps. It operates from a 2.5V or 3.3V supply (VCC = 2.375V to 3.8V, VEE = 0V) or negative ECL supply (VEE = -3.8V to -2.375V).

Feature Summary

• Dual 1-to-5 differential fanout buffer architecture supporting both ECL and LVPECL logic families.
• Wide input compatibility including LVDS, LVPECL, LVHSTL, SSTL, and HCSL differential signals.
• High-speed performance with 700MHz maximum output frequency and 1.7ns typical propagation delay.
• Low skew characteristics with 25ps typical output skew for precise clock distribution.

Applications

• Clock distribution in high-performance computing systems requiring defined repeatability.
• Server and storage architectures utilizing LVPECL or ECL backplane interfaces.
• Telecommunications equipment demanding low jitter and high-frequency signal integrity.

Procurement Notes

Verify component authenticity through authorized Renesas distributors due to potential counterfeit risks. Confirm RoHS compliance status as the package is lead-free. Check current lifecycle status as older generation clock buffers may face discontinuation notices. Ensure supply voltage requirements match the specific system design (2.5V vs 3.3V). Validate pinout compatibility if replacing legacy components from other manufacturers.

Selection Notes

Select this component when dual independent 1-to-5 fanout is required for differential clock networks. Choose based on the need for low skew (<25ps typ) and minimal jitter (<0.13ps RMS) in high-speed digital designs. Verify that the system power supply aligns with the 2.375V to 3.8V range for LVPECL operation. Consider thermal management as multiple outputs drive significant capacitive loads at 700MHz.

Part Context

This part belongs to the 85311I series of high-performance clock buffers. It serves as a critical interconnect component in complex digital systems where signal integrity across multiple branches is paramount. The device bridges various logic families, allowing flexible integration between different voltage domains in server and telecom infrastructure.

Replacement Considerations

Direct replacements must support dual 1-to-5 differential fanout with similar skew and jitter specifications. Verify pin-to-pin compatibility if substituting within the same package type. Ensure the alternative supports the required input formats (LVDS, LVPECL, etc.) and operating voltage ranges. Consult Renesas documentation for any updated family members with enhanced features.