FDMS3604AS MOSFET Equivalent & Substitute Parts

Part Overview

The FDMS3604AS is a dual N-channel MOSFET manufactured by onsemi, featuring a 30V drain-to-source voltage rating and continuous drain current capabilities of 13A and 23A. This component utilizes PowerTrench® technology in a 8-PowerTDFN surface mount package and is classified as obsolete. Due to its obsolete product status, identification of equivalent and substitute parts is necessary to maintain design continuity and ensure component availability for new production runs and legacy system support.

Substiute Parts

FDMS3604AS

onsemiIn Stock: 3466FDMS3604AS Datasheet

Current PartRFQ

FDMS3604S

onsemiIn Stock: 29236FDMS3604S Datasheet

DirectRFQ

STL66DN3LLH5

STMicroelectronicsIn Stock: 22720STL66DN3LLH5 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FDMS3604AS is determined by strict alignment of electrical and mechanical parameters. The primary substitution criteria are:

Direct Electrical Equivalence Parameters:

• Drain-to-source voltage (Vdss) must equal or exceed 30V
• Continuous drain current (Id) must support 13A and 23A ratings
• On-state resistance (Rds On) must not exceed 8mOhm at specified conditions
• Gate threshold voltage (Vgs(th)) must remain within acceptable logic-level gate specifications
• Configuration must be dual N-channel

Mechanical Compatibility Parameters:

• Surface mount mounting type
• Package footprint compatibility (8-PowerTDFN or equivalent)
• Moisture sensitivity level (MSL) rating of 1 or better

Compliance and Availability:

• Product status (Active preferred for new designs; Obsolete acceptable for legacy support)
• RoHS and REACH compliance status
• Current inventory availability

Substitute parts are grouped into two categories: direct equivalents (identical electrical and mechanical specifications with different packaging or product status) and similar alternatives (enhanced electrical performance with compatible package footprints).

Parameter Comparison

Engineering Selection Recommendations

FDMS3604S (Direct Equivalent - Recommended for Active Production)

The FDMS3604S is the primary substitute for the obsolete FDMS3604AS. This part maintains identical electrical specifications including 30V Vdss, 13A/23A continuous drain current, and 8mOhm on-state resistance. The FDMS3604S is manufactured by onsemi in the same PowerTrench® series and uses the identical 8-PowerTDFN package footprint. The critical distinction is product status: FDMS3604S is Active with ROHS3 compliance, making it suitable for new production designs. Packaging is available in Cut Tape and Digi-Reel® formats with 29,200 pieces in current inventory. This part requires no circuit redesign and provides direct pin-for-pin compatibility.

STL66DN3LLH5 (Similar Alternative - Enhanced Performance)

The STL66DN3LLH5 manufactured by STMicroelectronics is a similar alternative that maintains the 30V Vdss rating and logic-level gate feature. This part offers enhanced electrical performance with 78.5A continuous drain current (compared to 13A/23A), lower on-state resistance of 6.5mOhm, and significantly higher power dissipation capability of 72W. The STL66DN3LLH5 is qualified to AEC-Q101 automotive standards and operates across an extended temperature range of -55°C to 175°C. The package is 8-PowerVDFN (PowerFlat™ 5x6), which differs from the 8-PowerTDFN of the main part. This alternative is suitable for applications requiring higher current handling or automotive-grade qualification, provided PCB layout accommodates the different package footprint. Current inventory is 22,650 pieces.

Selection Criteria Summary:

• For direct replacement in existing designs: select FDMS3604S
• For new designs requiring active product status: select FDMS3604S
• For applications requiring automotive qualification or enhanced current capacity: evaluate STL66DN3LLH5 with PCB layout verification
• All three parts maintain MSL 1 (Unlimited) moisture sensitivity rating and REACH compliance

Frequently Asked Questions (FAQ)

Q: Can FDMS3604S be used as a direct replacement for FDMS3604AS?

A: Yes. The FDMS3604S is a direct electrical and mechanical equivalent. Both parts share identical Vdss (30V), Id (13A/23A), Rds On (8mOhm), Vgs(th) (2.7V), and gate charge (29nC) specifications. Both use the 8-PowerTDFN package with identical pinout. The primary difference is product status: FDMS3604AS is obsolete while FDMS3604S is active with ROHS3 compliance. No circuit modifications are required.

Q: What is the difference between FDMS3604S and STL66DN3LLH5?

A: Both parts maintain 30V Vdss and logic-level gate operation. The STL66DN3LLH5 provides significantly higher performance: 78.5A continuous drain current (versus 13A/23A), 6.5mOhm on-state resistance (versus 8mOhm), and 72W power dissipation (versus 1W). The STL66DN3LLH5 uses an 8-PowerVDFN package (PowerFlat™ 5x6) instead of 8-PowerTDFN, requiring PCB layout changes. The STL66DN3LLH5 includes AEC-Q101 automotive qualification and operates to 175°C (versus 150°C).

Q: Is the STL66DN3LLH5 package compatible with the FDMS3604AS footprint?

A: No. The STL66DN3LLH5 uses 8-PowerVDFN (PowerFlat™ 5x6) packaging while FDMS3604AS uses 8-PowerTDFN. These packages have different physical dimensions and pinout arrangements. PCB layout modification is required for STL66DN3LLH5 substitution. Verify footprint compatibility with your PCB design before selecting this alternative.

Q: Why is FDMS3604AS listed as obsolete?

A: FDMS3604AS is classified as obsolete by onsemi, indicating it is no longer in active production. The active equivalent FDMS3604S is available as a replacement. For new designs, FDMS3604S is recommended to ensure long-term component availability and compliance with current manufacturing standards.

Q: Are all three parts RoHS and REACH compliant?

A: FDMS3604S and STL66DN3LLH5 are ROHS3 compliant. FDMS3604AS is listed as REACH Unaffected. All three parts carry MSL 1 (Unlimited) moisture sensitivity ratings. For new production, FDMS3604S and STL66DN3LLH5 are preferred due to active ROHS3 compliance status.

Q: What is the gate charge difference between these parts?

A: FDMS3604AS and FDMS3604S both specify 29nC gate charge at 10V. STL66DN3LLH5 specifies 12nC gate charge at 4.5V. Lower gate charge reduces switching losses and driver power requirements. The STL66DN3LLH5 gate charge specification is measured at a different voltage (4.5V versus 10V), reflecting different device characteristics. Verify gate driver compatibility when selecting STL66DN3LLH5.

Q: Can I use STL66DN3LLH5 in a low-power application designed for FDMS3604AS?

A: Yes, electrically. The STL66DN3LLH5 maintains 30V Vdss and logic-level gate operation, making it electrically compatible. However, the significantly higher current rating (78.5A versus 13A/23A) and power dissipation (72W versus 1W) indicate this part is designed for higher-power applications. PCB layout must be modified to accommodate the different package footprint. Verify that your application can benefit from the enhanced performance specifications before substituting.

Q: What inventory is available for each part?

A: FDMS3604AS has 3,400 pieces in stock (obsolete status). FDMS3604S has 29,200 pieces available in Cut Tape and Digi-Reel® packaging. STL66DN3LLH5 has 22,650 pieces in stock. For new production, FDMS3604S offers the highest inventory availability with active product status.