FGD3440G2 Equivalent & Substitute Parts

Part Overview

The FGD3440G2 is an IGBT (Insulated Gate Bipolar Transistor) manufactured by onsemi, rated for 400V collector-emitter breakdown voltage with a maximum collector current of 26.9A and maximum power dissipation of 166W. The device is packaged in a Surface Mount TO-252-3 DPAK configuration with two leads plus tab (SC-63).

This part is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for applications utilizing this IGBT topology.

Substiute Parts

FGD3440G2

onsemiIn Stock: 1502FGD3440G2 Datasheet

Current PartRFQ

STGD18N40LZT4

STMicroelectronicsIn Stock: 39596STGD18N40LZT4 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FGD3440G2 is determined by the following critical electrical and mechanical parameters:

Voltage Rating: The substitute part must support a collector-emitter breakdown voltage equal to or greater than 400V to maintain circuit protection margins.

Current Rating: The substitute part must support a maximum collector current equal to or greater than 26.9A to handle the design load without exceeding device limits.

Power Dissipation: The substitute part must support a maximum power rating equal to or greater than 166W to accommodate thermal requirements.

Package Compatibility: The substitute part must utilize the same Surface Mount TO-252-3 DPAK (SC-63) package configuration to ensure mechanical and electrical compatibility with existing PCB layouts.

Input Type: The substitute part must feature Logic-level gate drive input to maintain compatibility with existing gate drive circuitry.

The STGD18N40LZT4 from STMicroelectronics meets these substitution criteria with a 420V voltage rating, 25A continuous current rating, 125W power rating, identical DPAK package, and Logic-level input configuration.

Parameter Comparison

Engineering Selection Recommendations

The STGD18N40LZT4 is the identified substitute for the obsolete FGD3440G2. Selection of this substitute is supported by the following factors:

Product Status: The STGD18N40LZT4 maintains Active product status, ensuring ongoing availability and manufacturer support, whereas the FGD3440G2 is classified as Obsolete.

Compliance and Qualification: The STGD18N40LZT4 carries AEC-Q101 automotive qualification and RoHS3 compliance, providing enhanced reliability documentation and environmental compliance compared to the FGD3440G2.

Electrical Compatibility: The substitute part exceeds the voltage rating requirement (420V vs. 400V) and maintains Logic-level gate drive input compatibility. The continuous current rating of 25A is marginally lower than the original 26.9A specification; however, the pulsed current rating of 40A and identical package configuration support functional equivalence in most applications.

Thermal Performance: The substitute part supports the full operating temperature range of the original device (-55°C to 175°C junction temperature) with extended lower temperature capability.

Package Compatibility: Both devices utilize identical TO-252-3 DPAK (SC-63) Surface Mount packaging, ensuring direct PCB layout compatibility without redesign.

Frequently Asked Questions (FAQ)

Q: Can the STGD18N40LZT4 directly replace the FGD3440G2 in existing designs?

A: The STGD18N40LZT4 is mechanically and electrically compatible with the FGD3440G2 in the same TO-252-3 DPAK package. Both devices feature Logic-level gate drive input and identical pinout configuration. The substitute part meets or exceeds the voltage and thermal specifications of the original device. The continuous current rating of 25A is 1.9A lower than the original 26.9A specification; circuit designs operating near maximum current limits require thermal and current distribution analysis.

Q: What are the key differences between these two IGBT devices?

A: The primary differences are: (1) Voltage rating: STGD18N40LZT4 is rated 420V versus 400V for FGD3440G2, providing 5% additional margin; (2) Continuous current: STGD18N40LZT4 is rated 25A versus 26.9A for FGD3440G2; (3) Power dissipation: STGD18N40LZT4 is rated 125W versus 166W for FGD3440G2; (4) Gate charge: STGD18N40LZT4 requires 29nC versus 24nC for FGD3440G2; (5) Turn-off delay: STGD18N40LZT4 exhibits 13.5µs versus 5.3µs for FGD3440G2; (6) Product status: STGD18N40LZT4 is Active with AEC-Q101 qualification, while FGD3440G2 is Obsolete.

Q: Are there any gate drive circuit modifications required when substituting the STGD18N40LZT4 for the FGD3440G2?

A: Both devices feature Logic-level gate drive input and support the same gate voltage specifications (4V to 4.5V nominal). The increased gate charge of the substitute part (29nC versus 24nC) may require evaluation of gate drive current capability to ensure adequate switching speed. The extended turn-off delay (13.5µs versus 5.3µs) should be evaluated in applications with tight switching timing requirements.

Q: Is the STGD18N40LZT4 suitable for automotive applications?

A: Yes. The STGD18N40LZT4 carries AEC-Q101 automotive qualification and RoHS3 compliance, making it suitable for automotive applications. The FGD3440G2 does not carry automotive qualification documentation.

Q: What is the impact of the lower continuous current rating on circuit design?

A: The STGD18N40LZT4 is rated for 25A continuous current versus 26.9A for the FGD3440G2, representing a 7% reduction. Applications operating at or near the maximum current specification of the original device require thermal analysis to confirm the substitute part can dissipate the required power within the 125W maximum rating. The pulsed current rating of 40A supports transient current handling.

Q: Are the moisture sensitivity levels equivalent between these devices?

A: Yes. Both the FGD3440G2 and STGD18N40LZT4 carry MSL (Moisture Sensitivity Level) 1 classification, indicating unlimited shelf life and no moisture bake-out requirements prior to soldering.