SSL5251T/1J LED Driver IC Equivalent & Substitute Parts

Part Overview

The SSL5251T/1J is an AC DC offline switcher LED driver IC manufactured by NXP USA Inc., designed for lighting applications with Triac dimming capability. This component integrates Step-Down (Buck) and Step-Up (Boost) topologies in an 8-SO surface mount package. The part is currently discontinued at DiGi Electronics, necessitating identification of functionally equivalent alternatives that maintain compatibility with existing designs while meeting the same electrical and mechanical specifications.

Substiute Parts

SSL5251T/1J

NXP USA Inc.In Stock: 1080SSL5251T/1J Datasheet

Current PartRFQ

MP4026GJ-P

Monolithic Power SystemsIn Stock: 1295MP4026GJ-P Datasheet

MFR RecommendedRFQ

RT8497BGS

Richtek USA Inc.In Stock: 2081RT8497BGS Datasheet

MFR RecommendedRFQ

TPS92074DR

Texas InstrumentsIn Stock: 5370TPS92074DR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SSL5251T/1J is determined by the following critical parameters:

• Type & Topology: AC DC offline switcher functionality with Step-Down (Buck) and/or Step-Up (Boost) capability
• Voltage Supply Range: Operating range must encompass or exceed 9.9V to 16V minimum specification
• Package Compatibility: Surface mount 8-pin packages (8-SOIC, 8-SOP, or equivalent footprint)
• Output Configuration: Single output LED driver IC
• Compliance: ROHS3 compliance and MSL rating suitable for standard manufacturing processes
• Application: Lighting-specific LED driver functionality

The three identified substitutes meet these criteria with variations in topology implementation, supply voltage range, and product status. Each maintains functional equivalence for AC DC offline LED driver applications while accommodating different design requirements.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: TPS92074DR (Texas Instruments)

The TPS92074DR is the preferred substitute for the SSL5251T/1J. It maintains identical topology (Buck and Boost), operates within the required voltage supply range (11V to 18V), and is housed in the same 8-SOIC package. The part is currently active in production with ROHS3 compliance and MSL-1 rating, ensuring long-term availability and manufacturing compatibility. Operating temperature range (-40°C to 125°C) meets the original specification requirements.

Secondary Substitute: MP4026GJ-P (Monolithic Power Systems)

The MP4026GJ-P provides AC DC offline switcher functionality with Flyback topology in an active product status. Supply voltage range (9.8V to 27V) encompasses the original specification. However, the SOT-23-6 package differs from the 8-SOIC footprint, requiring PCB layout modification. This option is suitable when package redesign is feasible and extended supply voltage range is beneficial.

Tertiary Substitute: RT8497BGS (Richtek)

The RT8497BGS is an obsolete part with Step-Down (Buck) topology only, lacking the Boost capability of the original SSL5251T/1J. While it maintains 8-SOIC package compatibility and ROHS3 compliance, its obsolete status and limited topology make it unsuitable for new designs. This part is listed for reference only and should not be selected for production applications.

Frequently Asked Questions (FAQ)

Q: Can the MP4026GJ-P be used as a direct replacement without PCB modifications?

A: No. The MP4026GJ-P uses SOT-23-6 packaging versus the SSL5251T/1J's 8-SOIC package. PCB layout and footprint redesign are required. Pin configuration and signal routing will differ.

Q: What is the primary difference between the TPS92074DR and SSL5251T/1J?

A: Both devices share identical AC DC offline switcher topology with Buck and Boost capability and 8-SOIC packaging. The TPS92074DR has a slightly higher minimum supply voltage (11V versus 9.9V) and lower maximum operating temperature (125°C versus 150°C). These differences are typically non-critical for standard lighting applications.

Q: Why is the RT8497BGS not recommended despite 8-SOIC package compatibility?

A: The RT8497BGS is obsolete and implements only Buck topology, eliminating Boost functionality present in the SSL5251T/1J. For designs requiring both topologies, this part is functionally incomplete. Its obsolete status also presents long-term supply chain risk.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All three substitute parts (MP4026GJ-P, RT8497BGS, and TPS92074DR) carry ROHS3 compliance certification, matching the original SSL5251T/1J specification.

Q: What is the significance of MSL rating differences between substitutes?

A: The SSL5251T/1J, MP4026GJ-P, and TPS92074DR carry MSL-1 (Unlimited) rating, suitable for standard manufacturing without moisture bake requirements. The RT8497BGS carries MSL-3 (168 Hours), requiring moisture control during storage and handling. For high-volume production, MSL-1 parts are preferred to reduce manufacturing complexity.

Q: Can the TPS92074DR operate at the SSL5251T/1J's minimum supply voltage of 9.9V?

A: No. The TPS92074DR minimum supply voltage is 11V, which exceeds the original part's 9.9V minimum. Designs operating below 11V require the MP4026GJ-P (9.8V minimum) or continued use of SSL5251T/1J inventory.