LNK6405D Equivalent & Substitute Parts

Part Overview

The LNK6405D is an offline switch flyback converter IC manufactured by Power Integrations, designed for isolated power supply applications. This device operates as part of the LinkSwitch™-3 series and delivers up to 5.1 W output power using flyback topology with integrated switching functionality.

The LNK6405D is discontinued at DiGi Electronics. Identifying equivalent substitute parts ensures design continuity and supply chain reliability for applications requiring this offline flyback converter topology.

Substiute Parts

LNK6405D

Power IntegrationsIn Stock: 2000LNK6405D Datasheet

Current PartRFQ

LNK6417D

Power IntegrationsIn Stock: 8605LNK6417D Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LNK6405D is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

• Topology: Flyback
• Output Isolation: Isolated
• Internal Switch(s): Yes
• Voltage - Breakdown: 725V
• Duty Cycle: 55%
• Frequency - Switching: Up to 85kHz
• Fault Protection: Current Limiting, Open Loop, Over Temperature, Short Circuit
• Operating Temperature: -40°C ~ 150°C (TJ)
• Package / Case: 8-SOIC (0.154", 3.90mm Width), 7 Leads
• Supplier Device Package: SO-8C
• Mounting Type: Surface Mount
• Series: LinkSwitch™-3

Variable Parameter (Allowable Difference):

• Power (Watts): The substitute part may have higher power rating than the main part, provided all other parameters remain identical.

The LNK6417D meets all mandatory matching parameters and is classified as a parametric equivalent with higher power output capability (7.5 W versus 5.1 W).

Parameter Comparison

Engineering Selection Recommendations

LNK6417D as Substitute for LNK6405D:

The LNK6417D is a direct parametric equivalent suitable for replacing the LNK6405D in offline flyback converter applications. Both devices share identical electrical specifications, thermal operating range, fault protection features, and physical packaging.

The LNK6417D provides higher power output capability (7.5 W versus 5.1 W) while maintaining all other critical parameters. This higher power rating does not create incompatibility; it represents enhanced performance headroom within the same device family and package footprint.

Both parts are RoHS Compliant and REACH Unaffected, meeting regulatory compliance requirements. The LNK6417D is currently available in higher inventory quantities (8563 Pcs) compared to the discontinued LNK6405D status.

Frequently Asked Questions (FAQ)

Q: Can the LNK6417D replace the LNK6405D in existing designs?

A: Yes. The LNK6417D is a parametric equivalent with identical topology, isolation, switching frequency, fault protection, operating temperature range, and package specifications. The higher power rating (7.5 W) does not create compatibility issues in applications designed for the 5.1 W LNK6405D.

Q: Are there any package or pinout differences between these parts?

A: No. Both the LNK6405D and LNK6417D use the 8-SOIC (0.154", 3.90mm Width) package with 7 leads and SO-8C supplier device package designation. PCB layout and component placement remain unchanged.

Q: What is the significance of the higher power rating on the LNK6417D?

A: The LNK6417D supports higher output power delivery (7.5 W) within the same electrical and thermal specifications. This provides additional design margin and performance capability without requiring circuit modifications.

Q: Are both parts compliant with environmental and regulatory standards?

A: Yes. Both the LNK6405D and LNK6417D are RoHS Compliant, REACH Unaffected, and carry MSL 1 (Unlimited) moisture sensitivity rating.

Q: What fault protection features are included in both devices?

A: Both parts include Current Limiting, Open Loop, Over Temperature, and Short Circuit fault protection mechanisms.