LNK409EG LED Driver IC Equivalent & Substitute Parts

Part Overview

The LNK409EG is an AC DC offline switcher LED driver IC manufactured by Power Integrations, designed for lighting applications requiring triac dimming capability. This device operates as a flyback topology converter with an internal switch, delivering 3.26A output current across a wide supply voltage range of 36V to 725V. The LNK409EG is classified as Active product status and is RoHS compliant with unlimited moisture sensitivity rating.

Substitute parts are necessary when the LNK409EG becomes unavailable, when alternative packaging or mounting requirements arise, or when design specifications allow for compatible topologies and electrical parameters. The following substitute parts maintain functional equivalence within defined parameter boundaries.

Substiute Parts

LNK409EG

Power IntegrationsIn Stock: 17240LNK409EG Datasheet

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MP4026GJ-P

Monolithic Power SystemsIn Stock: 1295MP4026GJ-P Datasheet

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RT8497BGS

Richtek USA Inc.In Stock: 2081RT8497BGS Datasheet

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TPS92411PDDAR

Texas InstrumentsIn Stock: 15459TPS92411PDDAR Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LNK409EG are selected based on the following critical parameters that determine functional equivalence:

Primary Substitution Criteria:

• Type: AC DC Offline Switcher (all substitutes match)
• Applications: Lighting (all substitutes match)
• Number of Outputs: 1 (all substitutes match)
• Internal Switch: Yes (required for direct substitution)
• Topology Compatibility: Flyback topology preferred; alternative topologies (Step-Down, Step-Up) acceptable if voltage and current ranges overlap

Secondary Compatibility Parameters:

• Voltage Supply Range: Substitutes must operate within or overlap the 36V to 725V range of the main part
• Output Current Capability: Substitutes must support minimum 3.26A or be suitable for reduced-current applications
• Dimming Capability: Triac dimming preferred; absence of dimming specification does not disqualify substitutes
• Operating Temperature Range: Substitutes must support -40°C to 150°C or equivalent industrial range
• Mounting Type: Through-hole preferred; surface-mount alternatives acceptable with PCB redesign
• Package Compatibility: eSIP-7C preferred; alternative packages acceptable with footprint adaptation

Regulatory Compliance:

• RoHS compliance required
• REACH unaffected status required
• EAR99 classification maintained

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: TPS92411PDDAR (Texas Instruments)

The TPS92411PDDAR is the preferred substitute for the LNK409EG based on the following factors:

• Product Status: Active, ensuring long-term availability and supply chain stability
• Topology Flexibility: Supports Flyback, Step-Down (Buck), and Step-Up (Boost) topologies, accommodating diverse circuit configurations
• Voltage Range: 7.5V to 94V supply range covers lower voltage applications; does not support the full 36V to 725V range of the main part
• Operating Temperature: -40°C to 150°C (TJ) matches the main part specification
• Internal Switch: Yes, eliminating external switching requirements
• Compliance: ROHS3 compliant, REACH unaffected, EAR99 classification
• Packaging: 8-SO PowerPad surface-mount package requires PCB redesign from through-hole eSIP-7C
• Inventory: 15,400 pieces in stock

Secondary Substitute: MP4026GJ-P (Monolithic Power Systems)

The MP4026GJ-P is suitable for reduced-voltage lighting applications:

• Product Status: Active
• Topology: Flyback topology matches the main part
• Voltage Range: 9.8V to 27V supply range limits application to low-voltage LED driver circuits
• Internal Switch: No, requiring external switching components
• Compliance: ROHS3 compliant, REACH unaffected, EAR99 classification
• Packaging: SOT-23-6 surface-mount package requires significant PCB redesign
• Inventory: 1,245 pieces in stock
• Temperature Limitation: 125°C maximum junction temperature is lower than the main part

Not Recommended: RT8497BGS (Richtek USA Inc.)

The RT8497BGS is not recommended as a substitute due to:

• Product Status: Obsolete, indicating discontinued production and limited future availability
• Output Current: 1.4A is significantly lower than the 3.26A of the main part
• Operating Temperature: -40°C to 85°C (TA) is lower than the main part specification
• Moisture Sensitivity: MSL 3 (168 Hours) indicates higher moisture sensitivity compared to MSL 1 of the main part
• Topology: Step-Down (Buck) topology differs from the Flyback topology of the main part

Frequently Asked Questions (FAQ)

Q1: Can the MP4026GJ-P directly replace the LNK409EG without circuit modifications?

No. The MP4026GJ-P has a maximum supply voltage of 27V compared to the LNK409EG's 725V maximum. Additionally, the MP4026GJ-P lacks an internal switch, requiring external switching components. PCB redesign is necessary for this substitution.

Q2: What is the primary limitation of using the TPS92411PDDAR as a substitute?

The TPS92411PDDAR has a maximum supply voltage of 94V, which does not cover the full 36V to 725V range of the LNK409EG. This substitute is suitable only for applications operating within the 7.5V to 94V range. Additionally, the TPS92411PDDAR uses surface-mount packaging (8-SO PowerPad) versus the through-hole eSIP-7C package of the main part, requiring PCB layout modifications.

Q3: Why is the RT8497BGS not recommended despite being listed as a substitute?

The RT8497BGS is obsolete, meaning it is no longer in production. This creates supply chain risk and limits long-term availability. Additionally, its 1.4A output current is insufficient for applications requiring the 3.26A capability of the LNK409EG. The lower operating temperature range (-40°C to 85°C) and higher moisture sensitivity (MSL 3) further limit its suitability.

Q4: Are all substitute parts RoHS compliant?

Yes. All substitute parts listed (MP4026GJ-P, RT8497BGS, TPS92411PDDAR) are RoHS3 compliant and REACH unaffected, matching the regulatory compliance of the LNK409EG.

Q5: What packaging considerations apply when substituting the LNK409EG?

The LNK409EG uses through-hole eSIP-7C packaging. All substitute parts use surface-mount packages (SOT-23-6 or 8-SO PowerPad), requiring PCB redesign including new footprints, trace routing, and potentially different thermal management approaches. Through-hole to surface-mount conversion is not a simple pin-for-pin substitution.

Q6: Can the LNK409EG be substituted in applications requiring triac dimming?

The LNK409EG explicitly supports triac dimming. The substitute parts (MP4026GJ-P, RT8497BGS, TPS92411PDDAR) do not specify dimming capability in their datasheets. Applications requiring triac dimming functionality should verify dimming support in the substitute part's detailed specifications before implementation.

Q7: Which substitute part has the closest operating temperature range to the LNK409EG?

The TPS92411PDDAR matches the LNK409EG operating temperature range of -40°C to 150°C (TJ). The MP4026GJ-P is limited to 125°C maximum, and the RT8497BGS is limited to -40°C to 85°C (TA).

Q8: What is the inventory status of each substitute part?

TPS92411PDDAR: 15,400 pieces in stock (highest availability) MP4026GJ-P: 1,245 pieces in stock RT8497BGS: 2,000 pieces in stock (not recommended due to obsolete status)