FDS6986AS Equivalent & Substitute Parts

Part Overview

The FDS6986AS is a dual N-channel MOSFET array manufactured by onsemi, designed for surface mount applications in 8-SOIC packaging. This device features logic level gate operation with a 30V drain-to-source voltage rating and continuous drain current capabilities of 6.5A to 7.9A. The part is classified as obsolete, necessitating identification of active equivalent alternatives for new designs and ongoing production requirements. Substitute parts must maintain compatibility across electrical specifications, package geometry, and thermal characteristics to ensure direct replacement capability.

Substiute Parts

FDS6986AS

onsemiIn Stock: 50348FDS6986AS Datasheet

Current PartRFQ

FDS8984

onsemiIn Stock: 27879FDS8984 Datasheet

MFR RecommendedRFQ

NTMD4820NR2G

onsemiIn Stock: 15464NTMD4820NR2G Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the FDS6986AS is determined by the following critical parameters:

Mandatory Compatibility Criteria:

• Drain to Source Voltage (Vdss): 30V minimum
• Configuration: 2 N-Channel (Dual) topology
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• FET Feature: Logic Level Gate operation
• Technology: MOSFET (Metal Oxide)
• Mounting Type: Surface Mount
• Operating Temperature Range: -55°C to 150°C (TJ)

Performance Parameters for Substitution Assessment:

• Current - Continuous Drain (Id) @ 25°C: Must meet or exceed application requirements
• Rds On (Max) @ Id, Vgs: Lower values indicate improved performance
• Gate Charge (Qg) (Max) @ Vgs: Affects switching speed and gate drive requirements
• Input Capacitance (Ciss) (Max) @ Vds: Influences input impedance characteristics
• Power - Max: Thermal dissipation capability

Substitute parts FDS8984 and NTMD4820NR2G satisfy all mandatory compatibility criteria and are therefore qualified as electrical and mechanical equivalents.

Parameter Comparison

Engineering Selection Recommendations

FDS8984 (MFR Recommended Substitute)

The FDS8984 is the manufacturer-recommended equivalent for the FDS6986AS. This part maintains identical voltage and package specifications while offering improved electrical performance characteristics. The FDS8984 delivers 7A continuous drain current with reduced on-resistance (23mOhm versus 29mOhm), lower gate charge (13nC versus 17nC), and increased power dissipation capability (1.6W versus 900mW). The device is classified as active product status, ensuring long-term availability and supply chain continuity. Full compliance with ROHS3, REACH, and MSL 1 certifications is maintained. The PowerTrench® series designation indicates advanced process technology implementation.

NTMD4820NR2G (Similar Manufacturer Substitute)

The NTMD4820NR2G provides an alternative substitute option with identical voltage and package compatibility. This device is rated for 4.9A continuous drain current and features the lowest on-resistance specification (20mOhm) among the three parts. Gate charge is significantly reduced (7.7nC), supporting faster switching applications. Power dissipation is rated at 750mW. The NTMD4820NR2G is classified as active product status with full ROHS3 and REACH compliance. Selection of this part is appropriate for applications where the lower current rating is sufficient and reduced gate charge characteristics provide system-level benefits.

Compliance and Regulatory Considerations

All substitute parts maintain identical regulatory compliance profiles: ROHS3 compliant, REACH unaffected, and MSL 1 (unlimited moisture sensitivity). ECCN classification remains EAR99 for all variants. These equivalencies ensure no regulatory or supply chain complications during part substitution.

Frequently Asked Questions (FAQ)

Q: Can FDS8984 directly replace FDS6986AS in existing designs?

A: Yes. The FDS8984 maintains identical drain-to-source voltage (30V), dual N-channel configuration, logic level gate operation, and 8-SOIC package geometry. All mandatory electrical and mechanical parameters are compatible. The part is manufacturer-recommended as the primary substitute.

Q: What are the key differences between FDS8984 and NTMD4820NR2G?

A: Both parts share identical voltage ratings and package specifications. FDS8984 provides 7A continuous drain current with 23mOhm on-resistance and 1.6W power dissipation. NTMD4820NR2G provides 4.9A continuous drain current with 20mOhm on-resistance and 750mW power dissipation. Selection depends on application current requirements and thermal constraints.

Q: Is the 8-SOIC package identical across all three parts?

A: Yes. All three parts use 8-SOIC packaging with 0.154" (3.90mm) width specification. PCB footprints and land patterns are identical, enabling direct physical substitution without layout modifications.

Q: Why is FDS6986AS classified as obsolete?

A: Product status reflects manufacturer discontinuation. FDS8984 and NTMD4820NR2G are active products with ongoing manufacturing and supply availability.

Q: Are there thermal performance differences between the substitutes?

A: Yes. FDS8984 supports 1.6W maximum power dissipation compared to FDS6986AS at 900mW and NTMD4820NR2G at 750mW. Applications with higher thermal budgets benefit from FDS8984 selection.

Q: Do gate charge differences affect circuit design?

A: Gate charge specifications influence gate drive circuit design and switching speed characteristics. FDS8984 (13nC) and NTMD4820NR2G (7.7nC) both feature reduced gate charge compared to FDS6986AS (17nC), supporting faster switching operation and reduced gate drive power requirements.

Q: Are all parts qualified for the full -55°C to 150°C operating temperature range?

A: Yes. All three parts maintain identical operating temperature specifications from -55°C to 150°C junction temperature, ensuring thermal compatibility across the full application range.

Q: What is the significance of Logic Level Gate operation?

A: Logic level gate operation indicates the parts are designed for direct interface with standard logic signal levels (typically 3.3V or 5V), eliminating the need for gate drive level shifting circuits in digital control applications.