Renesas 8521BYILF Clock Fanout Buffer Equivalent & Substitute Parts

Part Overview

The Renesas 8521BYILF is a clock fanout buffer (distribution) multiplexer IC designed for 2:9 signal distribution at frequencies up to 500 MHz. This device features differential input and output capabilities with support for multiple input standards including CML, HCSL, HSTL, LVDS, LVHSTL, LVPECL, and SSTL, with HSTL output configuration.

The 8521BYILF is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity and ensure component availability for new production runs and system upgrades.

Substiute Parts

8521BYILF

Renesas Electronics CorporationIn Stock: 9928521BYILF Datasheet

Current PartRFQ

SY89809ALTZ

Microchip TechnologyIn Stock: 2274SY89809ALTZ Datasheet

MFR RecommendedRFQ

SY898531LTZ

Microchip TechnologyIn Stock: 2106SY898531LTZ Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 8521BYILF are selected based on the following critical parameters that determine functional compatibility:

• Input:Output Ratio of 2:9
• Differential input and output capability
• Maximum frequency rating of 500 MHz or higher
• 32-pin TQFP package form factor
• Surface mount technology
• Supply voltage compatibility within or overlapping the 3.135V ~ 3.465V range

The substitute parts identified maintain the core 2:9 distribution architecture and differential signal processing capability. Variations in maximum frequency, output signal standard, and operating temperature range are noted as secondary parameters that may affect specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

SY89809ALTZ (Microchip Technology) is the manufacturer-recommended substitute for the 8521BYILF. This part maintains the 2:9 input:output ratio and differential signal architecture while offering enhanced frequency capability at 750 MHz. The SY89809ALTZ is classified as active product status with ROHS3 compliance and unlimited moisture sensitivity rating, providing superior long-term availability and environmental compliance compared to the obsolete 8521BYILF.

SY898531LTZ (Microchip Technology) provides an alternative substitute with matched 500 MHz frequency specification and identical supply voltage range. This part is also active product status with ROHS3 compliance. The SY898531LTZ differs in output signal standard (LVPECL versus HSTL) and operating temperature range (0°C ~ 70°C versus -40°C ~ 85°C), requiring verification of output signal compatibility and thermal operating envelope for specific applications.

Both Microchip substitutes are available in 32-TQFP packaging, which is mechanically compatible with the original 32-LQFP form factor for surface mount applications.

Frequently Asked Questions (FAQ)

Q: Can the SY89809ALTZ directly replace the 8521BYILF in existing designs?

A: The SY89809ALTZ maintains the 2:9 distribution ratio, differential input/output capability, and 32-pin TQFP package compatibility. However, the output signal standard differs (HSTL on 8521BYILF versus HSTL on SY89809ALTZ). Verify that downstream receiver circuits are compatible with the specified output standard before implementation.

Q: What is the difference between the two Microchip substitutes?

A: SY89809ALTZ operates at 750 MHz maximum frequency with HSTL output and 0°C ~ 85°C temperature range. SY898531LTZ operates at 500 MHz maximum frequency with LVPECL output and 0°C ~ 70°C temperature range. Select based on required frequency performance, output signal standard compatibility, and operating temperature requirements.

Q: Are there package compatibility concerns?

A: The original 8521BYILF uses 32-LQFP packaging. Both Microchip substitutes use 32-TQFP packaging. These packages are mechanically compatible for surface mount PCB assembly, though pin pitch and thermal characteristics should be verified against PCB design specifications.

Q: What compliance certifications apply to the substitute parts?

A: Both SY89809ALTZ and SY898531LTZ are ROHS3 compliant and REACH unaffected. Both carry EAR99 ECCN classification and 8542.39.0001 HTSUS code, matching the regulatory profile of the original 8521BYILF.

Q: How do operating temperature ranges affect substitution?

A: The 8521BYILF operates from -40°C ~ 85°C. SY89809ALTZ operates from 0°C ~ 85°C, and SY898531LTZ operates from 0°C ~ 70°C. Applications requiring operation below 0°C or above 70°C must verify compatibility with the selected substitute part's thermal specifications.