851021AYLF

Overview

The 851021AYLF is a 1-to-21 differential HCSL fanout buffer manufactured by Renesas Electronics. It translates various differential input signals (LVPECL, LVHSTL, LVDS, HCSL) to differential HCSL outputs without external bias networks. The device operates at a supply voltage of 3.3V with a maximum output frequency of 250MHz. Key electrical parameters include a maximum output skew of 395ps, part-to-part skew of 335ps, and output drift of 140ps. The VOH is specified at a maximum of 850mV. It is housed in a 64-pin TQFP package and supports an operating temperature range of 0°C to 70°C.

Feature Summary

• Translates any differential input signal levels to differential HCSL output levels without requiring external bias networks
• Provides twenty-one differential HCSL outputs with accurate crossover voltage and duty cycle
• Supports maximum output frequency of 250MHz with low skew characteristics
• Characterized for full 3.3V supply voltage operation

Applications

• PCI Express interface applications
• FBDIMM memory module interfacing

Procurement Notes

The 851021AYLF is classified as obsolete or end-of-life. Verification of availability requires checking authorized distributors for remaining stock or alternative sourcing channels. Ensure compliance with RoHS 6 lead-free standards and confirm the specific carrier type (tray) and moisture sensitivity level (MSL 3) required for handling and storage.

Selection Notes

Select this component when a high-channel-count differential HCSL fanout buffer is required for systems operating at frequencies up to 250MHz. It is suitable for designs needing translation from multiple differential logic families to HCSL. Verify that the 64-pin TQFP package fits the PCB layout constraints and that the 0°C to 70°C commercial temperature range meets the environmental requirements.

Part Context

This part belongs to the ICS8510xx series of differential clock buffers. It shares functional similarities with other models like the 851010 but offers a higher output count (21 vs 10). The 'AYLF' suffix indicates the specific package variant (TQFP), lead-free composition, and temperature range classification within the product line.

Replacement Considerations

As the part is obsolete, direct substitutes may be limited. Consider evaluating other members of the 8510xx series if pin compatibility allows, or consult manufacturer documentation for recommended obsolescence alternatives. No public confirmed substitute part numbers are listed in the provided data.