FDS6984AS Equivalent & Substitute Parts

Part Overview

The FDS6984AS is a dual N-channel MOSFET array manufactured by onsemi, designed for surface mount applications in 8-SOIC packaging. This device features a 30V drain-to-source voltage rating with continuous drain current capabilities of 5.5A and 8.5A, and is rated for 900mW maximum power dissipation. The FDS6984AS is classified as obsolete, making identification of equivalent and substitute parts essential for ongoing design support and production continuity. Substitute parts must maintain compatibility across electrical specifications, mechanical packaging, and thermal characteristics to ensure direct replacement capability.

Substiute Parts

FDS6984AS

onsemiIn Stock: 67583FDS6984AS Datasheet

Current PartRFQ

FDS6986AS

Fairchild SemiconductorIn Stock: 50378FDS6986AS Datasheet

DirectRFQ

CWDM305ND TR13 PBFREE

Central Semiconductor CorpIn Stock: 10845CWDM305ND TR13 PBFREE Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the FDS6984AS are classified based on strict electrical and mechanical compatibility criteria. All substitute candidates must satisfy the following requirements:

Mandatory Compatibility Criteria:

• Drain to Source Voltage (Vdss): 30V minimum
• Configuration: 2 N-Channel (Dual) MOSFET array
• Package: 8-SOIC surface mount with 0.154" (3.90mm) width
• Operating Temperature Range: -55°C to 150°C (TJ)
• Technology: MOSFET (Metal Oxide)
• Gate Threshold Voltage (Vgs(th)): 3V @ 250µA

Performance Parameters for Substitution:

• Continuous Drain Current (Id): Equal to or greater than 5.5A
• On-State Resistance (Rds On): Equal to or less than 31mOhm @ specified conditions
• Maximum Power Dissipation: Equal to or greater than 900mW

Substitute parts are grouped into two categories: Direct Manufacturer Substitutes (meeting or exceeding all electrical specifications) and Similar Manufacturer Substitutes (meeting core electrical and mechanical requirements with minor parameter variations).

Parameter Comparison

Engineering Selection Recommendations

FDS6986AS (Direct Manufacturer Substitute)

The FDS6986AS is classified as a direct substitute for the FDS6984AS. This part is manufactured by Fairchild Semiconductor and maintains active product status, ensuring ongoing availability and support. The FDS6986AS meets or exceeds all electrical specifications of the main part: it provides higher continuous drain current ratings (6.5A and 7.9A versus 5.5A and 8.5A), lower on-state resistance (29mOhm versus 31mOhm), and identical voltage and temperature ratings. Both parts share the same 8-SOIC package footprint and dual N-channel configuration. The FDS6986AS is suitable for direct replacement in applications where the FDS6984AS is currently specified.

CWDM305ND TR13 PBFREE (Similar Manufacturer Substitute)

The CWDM305ND TR13 PBFREE is classified as a similar substitute for the FDS6984AS. Manufactured by Central Semiconductor Corp, this part is in active production status and provides equivalent electrical performance within the specified parameter ranges. The CWDM305ND TR13 PBFREE maintains the same 30V Vdss rating, 3V gate threshold voltage, and 8-SOIC package configuration. The continuous drain current rating of 5.8A falls within the operational range of the main part, and the on-state resistance of 30mOhm is comparable. A notable advantage is the higher maximum power dissipation rating of 2W versus 900mW, providing additional thermal margin. This part is supplied in Tape & Reel packaging and is ROHS3 compliant with MSL 1 rating. The CWDM305ND TR13 PBFREE is suitable for applications requiring equivalent performance with enhanced thermal characteristics.

Compliance and Certification Considerations

Both substitute parts maintain compliance with RoHS3 standards and operate across the full -55°C to 150°C temperature range. The FDS6986AS status and compliance certifications are not fully specified in available documentation. The CWDM305ND TR13 PBFREE provides complete RoHS3 compliance and MSL 1 rating, matching the environmental and handling requirements of the original part.

Frequently Asked Questions (FAQ)

Q: Can the FDS6986AS be used as a direct replacement for the FDS6984AS in existing designs?

A: Yes. The FDS6986AS meets all electrical and mechanical compatibility requirements for direct substitution. Both parts feature identical 30V Vdss ratings, 3V gate threshold voltages, 8-SOIC packaging, and -55°C to 150°C operating temperature ranges. The FDS6986AS provides equal or superior performance across all specified parameters.

Q: What are the key differences between the FDS6986AS and CWDM305ND TR13 PBFREE?

A: Both parts are compatible substitutes with identical voltage ratings and package types. The primary differences are: (1) Continuous drain current: FDS6986AS provides 6.5A and 7.9A versus CWDM305ND TR13 PBFREE at 5.8A; (2) Maximum power dissipation: CWDM305ND TR13 PBFREE is rated at 2W versus 900mW for FDS6986AS; (3) Gate charge: CWDM305ND TR13 PBFREE has lower gate charge (6.3nC @ 5V) compared to FDS6986AS (17nC @ 10V); (4) Packaging format: CWDM305ND TR13 PBFREE is supplied in Tape & Reel format.

Q: Are there any thermal performance differences between these substitute parts?

A: The CWDM305ND TR13 PBFREE has a maximum power dissipation rating of 2W, compared to 900mW for both the FDS6984AS and FDS6986AS. This provides additional thermal headroom in applications with higher power requirements. All three parts operate across the same temperature range (-55°C to 150°C TJ).

Q: Do all substitute parts have the same gate threshold voltage?

A: Yes. All three parts—FDS6984AS, FDS6986AS, and CWDM305ND TR13 PBFREE—have identical gate threshold voltage specifications of 3V @ 250µA, ensuring compatible gate drive requirements.

Q: What is the significance of the 8-SOIC package specification?

A: The 8-SOIC package is a surface mount dual in-line package with 0.154" (3.90mm) width. All substitute parts use this identical package, ensuring mechanical compatibility with existing PCB layouts and assembly processes. No board redesign or rework is required when substituting between these parts.

Q: Are there any differences in on-state resistance that would affect circuit performance?

A: The on-state resistance values are comparable across all parts: FDS6984AS at 31mOhm @ 5.5A, FDS6986AS at 29mOhm @ 6.5A, and CWDM305ND TR13 PBFREE at 30mOhm @ 2.9A. These minor variations fall within acceptable engineering tolerances for most applications and do not require circuit redesign.

Q: Why is the FDS6984AS classified as obsolete?

A: The FDS6984AS is listed as obsolete by the manufacturer. The FDS6986AS and CWDM305ND TR13 PBFREE are both in active production status, making them preferred choices for new designs and ongoing production support.

Q: Can the CWDM305ND TR13 PBFREE be used in high-frequency switching applications?

A: The CWDM305ND TR13 PBFREE has a lower gate charge (6.3nC @ 5V) compared to the FDS6986AS (17nC @ 10V), which may provide advantages in high-frequency switching applications. However, substitution decisions must be based on specific circuit requirements and performance validation.

Q: Are all substitute parts RoHS3 compliant?

A: The FDS6984AS and CWDM305ND TR13 PBFREE are both explicitly listed as ROHS3 compliant. The FDS6986AS compliance status is not specified in available documentation.