STD35NF3LLT4 Equivalent & Substitute Parts

Part Overview

The STD35NF3LLT4 is an N-Channel 30V 35A MOSFET manufactured by STMicroelectronics in the STripFET™ II series, housed in a DPAK (TO-252-3) surface mount package. This device is classified as obsolete, necessitating identification of equivalent alternatives for ongoing production and maintenance applications. The part delivers 50W maximum power dissipation at the case temperature and operates across an extended temperature range of -55°C to 175°C. Due to its obsolete status, substitute components with compatible electrical and mechanical specifications are required for design continuity and component sourcing.

Substiute Parts

STD35NF3LLT4

STMicroelectronicsIn Stock: 7558STD35NF3LLT4 Datasheet

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AOD480

Alpha & Omega Semiconductor Inc.In Stock: 19766AOD480 Datasheet

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DMG4468LK3-13

Diodes IncorporatedIn Stock: 78485DMG4468LK3-13 Datasheet

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DMG4800LK3-13

Diodes IncorporatedIn Stock: 15414DMG4800LK3-13 Datasheet

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NTD20N03L27T4G

onsemiIn Stock: 15402NTD20N03L27T4G Datasheet

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NTD4813NHT4G

onsemiIn Stock: 40745NTD4813NHT4G Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the STD35NF3LLT4 is determined by strict alignment of the following critical parameters:

Mandatory Compatibility Criteria:

• FET Type: N-Channel topology
• Drain to Source Voltage (Vdss): 30V minimum rating
• Package / Case: TO-252-3 DPAK surface mount configuration
• Mounting Type: Surface Mount
• RoHS Status: ROHS3 Compliant
• Operating Temperature Range: Minimum -55°C to 175°C (or compatible subset)

Performance-Level Parameters:

• Current - Continuous Drain (Id): Rated capacity at or above application requirements
• Rds On (Max): On-state resistance characteristics
• Gate Charge (Qg): Switching speed and drive requirements
• Power Dissipation (Max): Thermal management capability

Substitute parts are grouped into two categories based on current rating alignment:

Category A - High Current Substitutes (≥20A): Parts with continuous drain current ratings of 20A or higher, suitable for applications requiring the full current capacity of the original STD35NF3LLT4.

Category B - Moderate Current Substitutes (9.7A–10A): Parts with lower continuous drain current ratings, applicable to designs where current requirements are reduced or where thermal constraints limit utilization of higher-rated devices.

All substitute parts maintain identical voltage ratings (30V Vdss), identical package geometry (DPAK TO-252-3), and equivalent compliance certifications (ROHS3, REACH Unaffected, EAR99).

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Active Product Status):

The NTD4813NHT4G (onsemi) and NTD20N03L27T4G (onsemi) are recommended as primary substitutes. Both devices maintain active product status, ensuring long-term availability and manufacturing support. The NTD4813NHT4G delivers 40A continuous drain current at case temperature, matching the thermal performance envelope of the STD35NF3LLT4 with superior on-state resistance (13 mOhm vs. 19.5 mOhm). The NTD20N03L27T4G provides 20A continuous drain current with 74W case temperature power dissipation, suitable for applications where current requirements are moderate. Both parts operate across the full -55°C to 175°C temperature range and maintain ROHS3 compliance.

The DMG4468LK3-13 and DMG4800LK3-13 (Diodes Incorporated) are active alternatives with lower current ratings (9.7A and 10A respectively). These devices are appropriate for designs where thermal or current constraints limit utilization of higher-rated components. Both maintain ROHS3 compliance and operate to -55°C to 150°C.

Secondary Substitute (Not For New Designs):

The AOD480 (Alpha & Omega Semiconductor Inc.) carries a "Not For New Designs" status and is suitable only for maintenance and repair of existing equipment. This device provides 25A continuous drain current at case temperature with 21W power dissipation capability. While electrically compatible, its product status restricts application to legacy system support.

Selection Criteria:

• For applications requiring maximum current capacity and thermal performance: NTD4813NHT4G
• For moderate current applications with active product support: NTD20N03L27T4G or DMG4800LK3-13
• For legacy system maintenance only: AOD480
• For new designs with reduced current requirements: DMG4468LK3-13 or DMG4800LK3-13

All recommended substitutes maintain identical 30V Vdss rating, DPAK package geometry, surface mount configuration, and ROHS3 compliance.

Frequently Asked Questions (FAQ)

Q: Can the NTD4813NHT4G directly replace the STD35NF3LLT4 in all applications?

A: The NTD4813NHT4G is electrically and mechanically compatible with the STD35NF3LLT4. Both devices share identical 30V Vdss rating, DPAK TO-252-3 package geometry, and surface mount configuration. The NTD4813NHT4G delivers superior on-state resistance (13 mOhm vs. 19.5 mOhm) and higher case temperature current rating (40A vs. 35A). The NTD4813NHT4G maintains active product status and operates across the full -55°C to 175°C temperature range. Direct substitution is supported without circuit modification.

Q: What is the difference between the two onsemi alternatives (NTD4813NHT4G and NTD20N03L27T4G)?

A: Both onsemi devices are active products with 30V Vdss rating and DPAK packaging. The NTD4813NHT4G provides 40A continuous drain current at case temperature with 13 mOhm on-state resistance, delivering higher current capacity and lower conduction losses. The NTD20N03L27T4G provides 20A continuous drain current at ambient temperature with 27 mOhm on-state resistance. Selection depends on application current requirements and thermal management strategy. The NTD4813NHT4G is preferred for high-current applications; the NTD20N03L27T4G is suitable for moderate-current designs.

Q: Why are the Diodes Incorporated parts (DMG4468LK3-13 and DMG4800LK3-13) rated at lower current levels?

A: The DMG4468LK3-13 and DMG4800LK3-13 are optimized for different application requirements than the STD35NF3LLT4. These devices deliver 9.7A and 10A continuous drain current respectively at ambient temperature, with correspondingly lower power dissipation ratings (1.68W and 1.71W). These parts are suitable for applications where current requirements are reduced or where thermal constraints limit utilization of higher-rated devices. Both maintain 30V Vdss rating, DPAK packaging, and ROHS3 compliance. Selection should be based on specific application current and thermal requirements.

Q: Is the AOD480 suitable for new product designs?

A: The AOD480 carries a "Not For New Designs" product status classification. This device is restricted to maintenance, repair, and support of existing equipment only. For new product development, select from active-status alternatives: NTD4813NHT4G, NTD20N03L27T4G, DMG4468LK3-13, or DMG4800LK3-13.

Q: Are all substitute parts ROHS3 compliant?

A: All substitute parts listed in this reference are ROHS3 compliant. The STD35NF3LLT4 and all identified alternatives meet ROHS3 environmental compliance requirements. All parts are also REACH Unaffected and classified as EAR99 for export control purposes.

Q: What is the significance of the different temperature ratings (175°C vs. 150°C)?

A: The STD35NF3LLT4, NTD4813NHT4G, and AOD480 operate to a maximum junction temperature of 175°C. The DMG4468LK3-13, DMG4800LK3-13, and NTD20N03L27T4G operate to a maximum junction temperature of 150°C. For applications requiring operation at elevated temperatures above 150°C, select NTD4813NHT4G or AOD480. For applications with thermal management limiting junction temperature to 150°C or below, all alternatives are suitable.

Q: How do the on-state resistance (Rds On) values compare across substitutes?

A: On-state resistance varies across substitute parts depending on current rating and measurement conditions. The NTD4813NHT4G delivers the lowest Rds On at 13 mOhm (measured at 30A, 10V gate voltage), providing superior conduction efficiency. The STD35NF3LLT4 specifies 19.5 mOhm at 17.5A, 10V. The DMG4800LK3-13 and DMG4468LK3-13 specify 17 mOhm and 16 mOhm respectively at their rated currents. Lower Rds On values reduce conduction losses and heat generation. Selection should account for application current levels and thermal budget requirements.

Q: Can substitute parts be used interchangeably in existing PCB layouts?

A: All substitute parts share identical DPAK TO-252-3 package geometry and surface mount configuration. PCB footprints, solder pad layouts, and thermal via patterns designed for the STD35NF3LLT4 are compatible with all listed substitutes without modification. Electrical connections (Gate, Drain, Source) follow identical pinout conventions across all DPAK devices. Direct PCB substitution is supported without layout revision.

Q: What inventory status should influence substitute selection?

A: Inventory availability varies across substitute parts. The NTD4813NHT4G (onsemi) maintains 40,700 units in stock. The NTD20N03L27T4G (onsemi) maintains 15,365 units. The DMG4468LK3-13 (Diodes Incorporated) maintains 78,400 units, the highest inventory level. The DMG4800LK3-13 (Diodes Incorporated) maintains 15,365 units. The AOD480 (Alpha & Omega Semiconductor Inc.) maintains 19,688 units. For applications requiring immediate availability, the DMG4468LK3-13 offers the largest stock position. For long-term production support, active-status alternatives (NTD4813NHT4G, NTD20N03L27T4G, DMG4468LK3-13, DMG4800LK3-13) are preferred over the "Not For New Designs" AOD480.