PL685-88DC Equivalent & Substitute Parts

Part Overview

The PL685-88DC is an IC clock buffer die manufactured by Microchip Technology, designed for 800MHz clock distribution applications. This component features a 1:2 input-to-output ratio with LVPECL output and operates from a 2.97V to 3.63V supply. The part is classified as obsolete, making identification of functionally compatible alternatives essential for ongoing system support and new design implementations.

Substiute Parts

PL685-88DC

Microchip TechnologyIn Stock: 943PL685-88DC Datasheet

Current PartRFQ

SY89831UMG

Microchip TechnologyIn Stock: 7102SY89831UMG Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PL685-88DC is determined by the following critical parameters:

• Output Type: LVPECL output compatibility is required for signal integrity in clock distribution circuits
• Frequency Range: The substitute must support the operational frequency of 800MHz or higher
• Supply Voltage: Operating voltage range must encompass or exceed the original 2.97V to 3.63V specification
• Number of Circuits: Single circuit configuration must be maintained
• Mounting Type: Surface mount compatibility for PCB integration

The SY89831UMG qualifies as a substitute based on these criteria. While it provides enhanced specifications (2GHz maximum frequency, 1:4 ratio capability, and extended temperature range), it maintains LVPECL output compatibility and operates within the required voltage envelope, making it suitable for applications previously served by the PL685-88DC.

Parameter Comparison

Engineering Selection Recommendations

The SY89831UMG is the manufacturer-recommended substitute for the obsolete PL685-88DC. Both components are manufactured by Microchip Technology and maintain ROHS3 compliance. The SY89831UMG offers superior performance specifications with a maximum frequency of 2GHz compared to the original 800MHz, and an extended operating temperature range of -40°C to 85°C versus 0°C to 70°C. The supply voltage range of 2.375V to 3.6V encompasses the original specification window. The transition from die form factor to 16-VFQFN packaging represents a standard industry evolution for clock buffer components, enabling improved thermal management and manufacturing consistency.

Frequently Asked Questions (FAQ)

Q: Can the SY89831UMG directly replace the PL685-88DC in existing designs?

A: The SY89831UMG provides functional equivalence for LVPECL clock distribution applications. The primary design consideration is the package transition from die form to 16-VFQFN. Existing die-based implementations require redesign for the packaged component, but electrical performance is compatible.

Q: What are the key differences between these parts?

A: The SY89831UMG provides higher frequency capability (2GHz vs 800MHz), a 1:4 output ratio option versus the 1:2 ratio of the PL685-88DC, and an extended operating temperature range. Both maintain LVPECL output compatibility and ROHS3 compliance.

Q: Is the supply voltage range compatible?

A: Yes. The SY89831UMG supply range of 2.375V to 3.6V overlaps with the PL685-88DC specification of 2.97V to 3.63V. Systems operating within the overlapping window (2.97V to 3.6V) require no supply circuit modifications.

Q: What packaging considerations apply to this substitution?

A: The PL685-88DC is supplied as a die, while the SY89831UMG is packaged in 16-VFQFN form factor. This represents a transition to a standard surface-mount package, improving handling, testing, and integration into modern manufacturing processes.

Q: Are both parts RoHS compliant?

A: Yes. Both the PL685-88DC and SY89831UMG are ROHS3 compliant, maintaining regulatory compliance for applications subject to RoHS requirements.