TFS757HG Equivalent & Substitute Parts Reference

Part Overview

The TFS757HG is an offline converter IC manufactured by Power Integrations, designed for isolated flyback and forward topology applications with 66kHz switching frequency and 193W power handling capability. This component operates as a complete power management solution with integrated switching functionality, internal fault protection, and dual voltage breakdown ratings (530V, 725V).

The TFS757HG is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for applications currently utilizing this topology.

Substiute Parts

TFS757HG

Power IntegrationsIn Stock: 5117TFS757HG Datasheet

Current PartRFQ

TFS7701H

Power IntegrationsIn Stock: 1175TFS7701H Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TFS757HG is determined by the following critical parameters:

Topology Compatibility: Both the main part and substitute must support Flyback and Forward converter topologies to maintain circuit functionality.

Output Isolation: The substitute must provide isolated output configuration to preserve galvanic isolation requirements in the application.

Switching Frequency: Operating frequency must be 66kHz or compatible harmonic frequencies (132kHz acceptable as higher frequency variant).

Supply Voltage Range: The substitute supply voltage specification must overlap or encompass the 11.1V ~ 13.4V operating range of the TFS757HG.

Package Compatibility: Both parts utilize 16-SSIP through-hole packages with exposed pad and formed leads, ensuring mechanical and electrical compatibility on existing PCB layouts.

Fault Protection: The substitute must include equivalent protection features (current limiting, over-temperature, over-voltage, short-circuit protection).

Control Features: Enable (EN) control functionality must be present in the substitute.

Operating Temperature Range: The substitute must support the full -40°C ~ 150°C junction temperature range.

Regulatory Compliance: Both parts must maintain RoHS compliance and REACH unaffected status.

The TFS7701H meets these substitution criteria as an active product within the HiperTFS™-2 series, offering compatible topology, isolation capability, frequency options, and package specifications.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: TFS7701H is the qualified equivalent for TFS757HG applications.

Justification Based on Provided Parameters:

The TFS7701H substitution is supported by the following factors:

1. Product Status Alignment: The TFS7701H is an active product, ensuring long-term availability and supply chain continuity compared to the obsolete TFS757HG.

2. Regulatory Compliance: Both parts maintain identical RoHS compliance and REACH unaffected status, satisfying regulatory requirements without modification.

3. Topology and Isolation: Both parts support Flyback and Forward converter topologies with isolation capability, preserving the functional architecture of existing designs.

4. Package Compatibility: Identical 16-SSIP through-hole package specifications with exposed pad and formed leads enable direct PCB layout compatibility.

5. Operating Temperature Range: Both parts support the full -40°C ~ 150°C junction temperature range, maintaining thermal performance specifications.

6. Control Features: The TFS7701H includes Enable and Reset control features, providing equivalent or enhanced control functionality compared to the TFS757HG's Enable-only specification.

7. Switching Frequency: The 66kHz switching frequency option in the TFS7701H matches the TFS757HG specification.

Design Verification Requirements:

Applications operating at the maximum 70% duty cycle of the TFS757HG must be evaluated against the TFS7701H maximum duty cycle specification of 63%. Supply voltage specifications must be confirmed within the overlapping range of 11.1V to 11.5V.

Frequently Asked Questions (FAQ)

Q: Can TFS7701H directly replace TFS757HG in existing PCB designs?

A: The TFS7701H is mechanically compatible with existing TFS757HG PCB layouts due to identical 16-SSIP through-hole package specifications. However, electrical design verification is required to confirm duty cycle and supply voltage compatibility within your specific application parameters.

Q: What is the primary difference between TFS757HG and TFS7701H?

A: The TFS757HG is an obsolete offline converter IC with integrated switching capability, while the TFS7701H is an active regulator controller IC with step-up/step-down functionality. Both support Flyback and Forward topologies with isolated output configuration. The TFS7701H offers enhanced control features (Enable and Reset) and represents the current generation HiperTFS™-2 series.

Q: Are there package differences between eSIP-16B and eSIP-16F?

A: Both eSIP-16B and eSIP-16F are 16-pin through-hole packages with 12 leads, exposed pad, and formed leads. The variant designation (B vs. F) indicates different internal die or lead frame configurations, but both maintain identical external package dimensions and PCB footprint compatibility.

Q: What duty cycle limitations apply when substituting TFS7701H for TFS757HG?

A: The TFS757HG operates at 70% duty cycle, while the TFS7701H maximum duty cycle is 63%. Applications designed for the full 70% duty cycle of the TFS757HG must be re-evaluated and potentially redesigned to operate within the 63% maximum of the TFS7701H.

Q: Are both parts RoHS compliant?

A: Yes, both TFS757HG and TFS7701H are RoHS compliant and REACH unaffected, meeting current regulatory requirements for electronic component manufacturing and use.

Q: What switching frequency options are available with TFS7701H?

A: The TFS7701H supports both 66kHz and 132kHz switching frequencies. The 66kHz option provides direct frequency matching with the TFS757HG specification.

Q: Is the TFS7701H suitable for isolated output applications?

A: Yes, the TFS7701H is specified as isolation capable and supports isolated output configuration, maintaining the galvanic isolation requirements of applications originally designed for the TFS757HG.

Q: What is the supply voltage compatibility range for substitution?

A: The TFS757HG operates at 11.1V ~ 13.4V supply voltage, while the TFS7701H operates up to 11.5V. The overlapping range is 11.1V to 11.5V. Applications requiring supply voltages above 11.5V cannot use the TFS7701H as a direct substitute.