LNK458VG LED Driver IC Equivalent & Substitute Parts

Part Overview

The LNK458VG is an AC DC offline switcher LED driver IC manufactured by Power Integrations, designed for TRIAC dimming applications with 1A output capability. This component operates in the LinkSwitch®-PL series and is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production support. The part delivers 1A output current at 122kHz frequency with integrated internal switching capability, housed in a 12-SDIP eDIP-12 package with exposed pad.

Substiute Parts

LNK458VG

Power IntegrationsIn Stock: 3261LNK458VG Datasheet

Current PartRFQ

AL1677-20BS-13

Diodes IncorporatedIn Stock: 6780AL1677-20BS-13 Datasheet

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LT3799IMSE#PBF

Analog Devices Inc.In Stock: 2589LT3799IMSE#PBF Datasheet

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UCC25710DW

Texas InstrumentsIn Stock: 952UCC25710DW Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the LNK458VG is determined by the following critical parameters: AC DC offline switcher topology, single output configuration, TRIAC dimming capability, and through-hole or surface-mount packaging compatibility. The substitute parts identified maintain functional equivalence in LED driver applications while accommodating different topologies, output current ratings, and package types.

Key substitution criteria:

• Type: AC DC Offline Switcher
• Number of Outputs: 1
• Dimming Method: TRIAC or PWM
• Internal Switch Configuration: Yes or No
• Operating Temperature Range: Minimum -40°C
• RoHS Compliance: Required

The three substitute parts listed represent different design approaches: AL1677-20BS-13 offers higher current capacity with step-down topology, LT3799IMSE#PBF provides TRIAC dimming with flyback topology, and UCC25710DW delivers PWM dimming control for backlight and lighting applications.

Parameter Comparison

Engineering Selection Recommendations

AL1677-20BS-13 (Diodes Incorporated): This substitute is suitable for applications requiring higher output current (2A vs. 1A) with step-down topology. The part is active and ROHS3 compliant. However, it lacks TRIAC dimming capability and operates at lower maximum supply voltage (16.2V vs. 50V). This part is appropriate for designs where dimming is not required and supply voltage remains below 16.2V.

LT3799IMSE#PBF (Analog Devices Inc.): This substitute maintains TRIAC dimming functionality and operates across a wider frequency range (25kHz to 300kHz). The part is active, ROHS3 compliant, and features an exposed pad in 16-TFSOP package. It uses flyback topology without internal switching, requiring external switch implementation. This part is appropriate for TRIAC dimming applications where surface-mount packaging is acceptable.

UCC25710DW (Texas Instruments): This substitute provides PWM dimming control suitable for backlight and lighting applications. The part is active, ROHS3 compliant, and housed in 20-SOIC surface-mount package. It operates at lower maximum supply voltage (18V vs. 50V) and lacks internal switching. This part is appropriate for PWM-controlled dimming applications where supply voltage remains below 18V.

All three substitutes are active products with current manufacturing support and full RoHS3 compliance, addressing the obsolescence of the LNK458VG.

Frequently Asked Questions (FAQ)

Q: Can AL1677-20BS-13 directly replace LNK458VG in existing designs?

A: AL1677-20BS-13 is not a direct replacement. While both are AC DC offline switcher LED drivers with single output, AL1677-20BS-13 lacks TRIAC dimming capability and operates at lower maximum supply voltage (16.2V vs. 50V). Circuit redesign is required if TRIAC dimming is essential to the application.

Q: What is the primary difference between LT3799IMSE#PBF and LNK458VG?

A: LT3799IMSE#PBF uses flyback topology without internal switching, whereas LNK458VG includes internal switching. LT3799IMSE#PBF maintains TRIAC dimming functionality but requires external switch implementation. Both operate across different frequency ranges and package types (surface-mount vs. through-hole).

Q: Is UCC25710DW suitable for TRIAC dimming applications?

A: No. UCC25710DW implements PWM dimming control, not TRIAC dimming. It is designed for backlight and lighting applications requiring PWM-based brightness control. For TRIAC dimming applications, LT3799IMSE#PBF is the appropriate substitute.

Q: What are the packaging implications when substituting LNK458VG?

A: LNK458VG uses through-hole 12-SDIP eDIP-12 packaging. All three substitutes use surface-mount packages (8-SOIC, 16-TFSOP, or 20-SOIC). PCB layout and assembly process modifications are required when transitioning from through-hole to surface-mount technology.

Q: Are all substitute parts RoHS compliant?

A: Yes. LNK458VG is RoHS Compliant. All three substitutes (AL1677-20BS-13, LT3799IMSE#PBF, and UCC25710DW) are ROHS3 Compliant, meeting current environmental and regulatory requirements.

Q: Which substitute offers the highest output current capability?

A: AL1677-20BS-13 provides 2A output current, compared to LNK458VG's 1A. However, output current specifications are not provided for LT3799IMSE#PBF and UCC25710DW, limiting direct current comparison across all substitutes.

Q: Can LT3799IMSE#PBF operate at the same supply voltage as LNK458VG?

A: Supply voltage specifications are not provided for LT3799IMSE#PBF, preventing direct voltage range comparison. Design verification is required to confirm compatibility with the intended supply voltage range.