Renesas 8543BGLF Clock Fanout Buffer Equivalent & Substitute Parts

Part Overview

The Renesas 8543BGLF is a Clock Fanout Buffer (Distribution) Multiplexer IC with 2:4 ratio capability operating at 800 MHz maximum frequency. This device features differential input and output support with multiple input protocol compatibility (CML, HCSL, LVDS, LVHSTL, LVPECL, SSTL) and LVDS output configuration. The 8543BGLF is classified as obsolete product status, making identification of active substitute components essential for new designs and ongoing production support.

Substiute Parts

8543BGLF

Renesas Electronics CorporationIn Stock: 12498543BGLF Datasheet

Current PartRFQ

8P34S1204NLGI

Renesas Electronics CorporationIn Stock: 10003208P34S1204NLGI Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 8543BGLF is determined by the following critical parameters:

Functional Equivalence Criteria:

• Input:Output ratio of 2:4
• Differential input and output configuration
• LVDS output protocol support
• Clock/Timing category classification

Performance Compatibility Criteria:

• Maximum frequency capability must meet or exceed 800 MHz operational requirement
• Supply voltage compatibility or dual-voltage support
• Operating temperature range suitable for application environment

Physical & Compliance Criteria:

• Surface mount packaging
• RoHS3 compliance
• REACH compliance status

The substitute part 8P34S1204NLGI meets all functional equivalence criteria with enhanced performance specifications. This part operates at 1.2 GHz maximum frequency, exceeding the 800 MHz requirement of the 8543BGLF. The 8P34S1204NLGI maintains 2:4 ratio, differential input/output configuration, and LVDS output protocol. However, the substitute features a different package type (16-VFQFN versus 20-TSSOP) and expanded supply voltage options, requiring PCB layout and schematic redesign.

Parameter Comparison

Engineering Selection Recommendations

Product Status Consideration: The 8543BGLF is classified as obsolete, indicating discontinued manufacturing and limited long-term availability. The 8P34S1204NLGI maintains active product status with Renesas Electronics Corporation, ensuring ongoing supply chain support and manufacturing continuity.

Compliance & Certification: Both parts maintain ROHS3 compliance and REACH unaffected status, satisfying environmental and regulatory requirements. The 8P34S1204NLGI features expanded operating temperature range (-40°C to 85°C) compared to the 8543BGLF (0°C to 70°C), providing broader application flexibility.

Design Integration Requirements: Selection of the 8P34S1204NLGI as a substitute requires PCB redesign due to package change from 20-TSSOP to 16-VFQFN. Supply voltage modification is necessary, as the substitute operates at 1.71V–1.89V or 2.1V–2.7V versus the original 3.135V–3.465V specification. Input protocol support is reduced to CML and LVDS on the substitute part.

Frequently Asked Questions (FAQ)

Q: Can the 8P34S1204NLGI directly replace the 8543BGLF without PCB modification?

A: No. The 8P34S1204NLGI uses a 16-VFQFN package with different pinout and physical dimensions compared to the 20-TSSOP package of the 8543BGLF. PCB layout redesign is required for mechanical and electrical compatibility.

Q: What are the key functional differences between these parts?

A: Both parts maintain 2:4 ratio, differential input/output configuration, and LVDS output protocol. The 8P34S1204NLGI operates at higher maximum frequency (1.2 GHz versus 800 MHz) and supports reduced input protocol options (CML, LVDS only versus CML, HCSL, LVDS, LVHSTL, LVPECL, SSTL).

Q: Are supply voltage requirements compatible?

A: No. The 8543BGLF requires 3.135V–3.465V supply voltage, while the 8P34S1204NLGI operates at 1.71V–1.89V or 2.1V–2.7V. Power supply circuit redesign is necessary for substitution.

Q: What is the impact of the different Moisture Sensitivity Level (MSL) ratings?

A: The 8543BGLF has MSL 1 (unlimited shelf life), while the 8P34S1204NLGI has MSL 3 (168-hour limit after moisture exposure). The substitute part requires stricter moisture control during storage and handling to maintain component reliability.

Q: Does the 8P34S1204NLGI support all input protocols of the 8543BGLF?

A: No. The 8P34S1204NLGI supports CML and LVDS input protocols only. If your application requires HCSL, LVHSTL, LVPECL, or SSTL input support, the 8P34S1204NLGI is not functionally equivalent for those specific input configurations.

Q: What is the operating temperature range difference?

A: The 8543BGLF operates from 0°C to 70°C, while the 8P34S1204NLGI operates from -40°C to 85°C. The substitute part provides extended low-temperature and high-temperature capability suitable for broader environmental applications.