LT3757IMSE Equivalent & Substitute Parts

Part Overview

The LT3757IMSE is a Boost, Flyback, and SEPIC regulator controller manufactured by Analog Devices Inc., designed for positive and negative output step-up and step-up/step-down DC-DC conversion applications. This device functions as a transistor driver with integrated control features including enable, frequency control, and soft start capabilities.

The LT3757IMSE is classified as an obsolete product. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for applications utilizing this DC-DC controller topology.

Substiute Parts

LT3757IMSE

Analog Devices Inc.In Stock: 2769LT3757IMSE Datasheet

Current PartRFQ

LT3757IMSE#PBF

Analog Devices Inc.In Stock: 2174LT3757IMSE#PBF Datasheet

DirectRFQ

LT3757AEMSE#PBF

Analog Devices Inc.In Stock: 2304LT3757AEMSE#PBF Datasheet

Parametric EquivalentRFQ

LT3757AEMSE#WPBF

Analog Devices Inc.In Stock: 1105LT3757AEMSE#WPBF Datasheet

Parametric EquivalentRFQ

LT3757AIMSE#PBF

Analog Devices Inc.In Stock: 4333LT3757AIMSE#PBF Datasheet

Parametric EquivalentRFQ

LT3757EMSE#PBF

Analog Devices Inc.In Stock: 8456LT3757EMSE#PBF Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LT3757IMSE is determined by strict equivalence across the following critical parameters:

Electrical Equivalence Criteria:

• Identical base product number (LT3757)
• Matching output type (Transistor Driver)
• Identical function (Step-Up, Step-Up/Step-Down)
• Matching output configuration (Positive and Negative)
• Identical topology (Boost, Flyback, SEPIC)
• Matching supply voltage range (2.9V ~ 40V)
• Identical switching frequency range (100kHz ~ 1MHz)
• Matching control features (Enable, Frequency Control, Soft Start)
• Identical operating temperature range (-40°C ~ 125°C)

Mechanical Equivalence Criteria:

• Identical mounting type (Surface Mount)
• Identical package specification (10-MSOP-EP)
• Matching physical dimensions (0.118", 3.00mm Width with Exposed Pad)

Environmental & Compliance Criteria:

• Identical moisture sensitivity level (MSL 1)
• Matching ECCN classification (EAR99)
• Matching HTSUS code (8542.39.0001)

All substitute parts listed maintain full electrical, mechanical, and environmental equivalence to the main part number. Differences in product status, packaging format (tube vs. reel), and optional automotive qualification do not affect functional interchangeability in applications designed for the LT3757 controller.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: LT3757EMSE#PBF

The LT3757EMSE#PBF is the preferred substitute for the obsolete LT3757IMSE. This part maintains complete electrical and mechanical equivalence while offering the highest inventory availability (8,400 units). The device carries active product status, ROHS3 compliance, and REACH unaffected designation, ensuring regulatory alignment for current manufacturing standards.

Secondary Recommendation: LT3757AIMSE#PBF

The LT3757AIMSE#PBF provides equivalent functionality with substantial inventory support (4,300 units) and active product status. This part is suitable for applications requiring standard industrial temperature range operation and standard compliance certifications.

Automotive Applications: LT3757AEMSE#WPBF

For applications requiring automotive-grade components, the LT3757AEMSE#WPBF is the designated substitute. This variant carries AEC-Q100 qualification and automotive grade designation, meeting automotive industry reliability and qualification standards. Inventory availability is 1,067 units.

Alternative Compliance Option: LT3757AEMSE#PBF

The LT3757AEMSE#PBF offers equivalent performance with 2,200 units in stock. This part is suitable for applications where automotive qualification is not required but enhanced reliability margins are desired.

Direct Packaging Equivalent: LT3757IMSE#PBF

The LT3757IMSE#PBF represents the direct tube-packaged equivalent of the main part number, with 2,140 units available. This part maintains identical electrical specifications and is suitable for direct replacement in existing designs.

All substitute parts are manufactured by Analog Devices Inc. and share the identical 10-MSOP-EP package specification, ensuring mechanical compatibility without PCB redesign.

Frequently Asked Questions (FAQ)

Q: Can I use LT3757EMSE#PBF as a direct replacement for LT3757IMSE?

A: Yes. The LT3757EMSE#PBF is electrically and mechanically equivalent to the LT3757IMSE. Both devices share identical electrical specifications, control features, operating temperature range, and 10-MSOP-EP package configuration. The primary difference is product status (active vs. obsolete) and compliance certifications.

Q: What is the difference between LT3757IMSE#PBF and LT3757AIMSE#PBF?

A: Both parts are electrically equivalent and share identical functional specifications. The difference lies in the part number designation (I-grade vs. A-grade), which may reflect different manufacturing test parameters or qualification levels. Both are active products with ROHS3 compliance and REACH unaffected status.

Q: Is the LT3757AEMSE#WPBF suitable for non-automotive applications?

A: Yes. The LT3757AEMSE#WPBF is functionally equivalent to all other LT3757 variants and operates identically in non-automotive applications. The automotive grade and AEC-Q100 qualification represent additional certifications that do not restrict use in standard industrial or consumer applications.

Q: Do all substitute parts use the same 10-MSOP-EP package?

A: Yes. All listed substitute parts utilize the identical 10-MSOP-EP package with 0.118" (3.00mm) width and exposed pad. No PCB layout modifications are required when substituting between any of these part numbers.

Q: What does the #PBF and #WPBF suffix indicate?

A: The #PBF suffix indicates lead-free, RoHS-compliant packaging. The #WPBF suffix indicates lead-free, RoHS-compliant packaging with automotive-grade qualification. Both suffixes denote compliance with current environmental and regulatory standards.

Q: Are all substitute parts ROHS3 compliant?

A: All active substitute parts (LT3757IMSE#PBF, LT3757AIMSE#PBF, LT3757EMSE#PBF, LT3757AEMSE#PBF, and LT3757AEMSE#WPBF) carry ROHS3 compliance designation. The original LT3757IMSE does not specify RoHS status.

Q: Can I mix different LT3757 variants in the same production run?

A: Yes. All listed variants are electrically and mechanically equivalent and can be used interchangeably in the same circuit design and PCB layout. However, design documentation should specify the selected part number for traceability and supply chain management.

Q: What is the operating temperature range for all substitute parts?

A: All substitute parts operate across the identical temperature range of -40°C to 125°C (junction temperature). This specification applies uniformly across all LT3757 variants listed.

Q: Are there any differences in switching frequency capability between variants?

A: No. All LT3757 variants support identical switching frequency range of 100kHz to 1MHz. Frequency selection is determined by external circuit design, not by part number variant.

Q: Which substitute part has the highest inventory availability?

A: The LT3757EMSE#PBF has the highest inventory availability with 8,400 units in stock, followed by LT3757AIMSE#PBF with 4,300 units.