LM3445M/NOPB LED Driver IC Equivalent & Substitute Parts

Part Overview

The LM3445M/NOPB is an AC DC offline switcher LED driver IC manufactured by Texas Instruments, designed for lighting applications with Triac dimming capability. This 14-SOIC surface mount device operates across 8V to 12V supply voltage with a step-down (buck) topology and switching frequency range of 30kHz to 1MHz. The part is currently active in production with ROHS3 compliance and unlimited moisture sensitivity rating.

Substitute parts are identified when design requirements necessitate alternative packaging formats, different supply voltage ranges, alternative dimming methods, or when primary part availability is constrained. The following equivalent devices maintain functional compatibility within specified electrical and mechanical parameters.

Substiute Parts

LM3445M/NOPB

Texas InstrumentsIn Stock: 1437LM3445M/NOPB Datasheet

Current PartRFQ

LT3799EMSE-1#PBF

Analog Devices Inc.In Stock: 25435LT3799EMSE-1#PBF Datasheet

MFR RecommendedRFQ

MXHV9910BTR

IXYS Integrated Circuits DivisionIn Stock: 2324MXHV9910BTR Datasheet

MFR RecommendedRFQ

RT8402GJ6

Richtek USA Inc.In Stock: 3650RT8402GJ6 Datasheet

MFR RecommendedRFQ

RT8458AGJ6

Richtek USA Inc.In Stock: 56124RT8458AGJ6 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility is determined by the following critical parameters:

Primary Substitution Criteria:

• AC DC offline switcher topology classification
• Single output configuration
• Triac or PWM dimming capability for lighting applications
• Surface mount packaging format
• Operating temperature range compatibility (-40°C minimum, 125°C or 85°C maximum)
• ROHS3 compliance and MSL rating 1 or 3
• Supply voltage overlap or extended range capability

Grouping Logic:

Group 1 - Triac Dimming, Step-Down Topology: RT8402GJ6, RT8458AGJ6, and MXHV9910BTR maintain Triac or PWM dimming with step-down (buck) topology. These parts accommodate the core lighting application requirement with alternative package formats (TSOT-23-6 or 8-SOIC) and extended supply voltage ranges.

Group 2 - Flyback Topology Alternative: LT3799EMSE-1#PBF provides Triac dimming with flyback topology in 16-MSOP-EP packaging. This topology variant serves equivalent functional requirements with different circuit architecture.

Parameter Comparison

Engineering Selection Recommendations

LT3799EMSE-1#PBF (Analog Devices Inc.): Active product status with ROHS3 compliance and unlimited MSL rating. Flyback topology provides alternative circuit architecture while maintaining Triac dimming and single output configuration. Suitable for designs requiring 16-MSOP-EP packaging with extended frequency range (25kHz to 300kHz). Supply voltage parameters not specified in available data.

MXHV9910BTR (IXYS Integrated Circuits Division): Active product with ROHS3 compliance and unlimited MSL rating. Step-down topology with PWM dimming in 8-SOIC package. Extended supply voltage range (8V to 450V) accommodates broader input specifications. Operating temperature maximum of 85°C (TA) represents reduced thermal specification compared to primary part. Suitable for signage applications.

RT8402GJ6 (Richtek USA Inc.): Obsolete product status. Step-down topology with Triac dimming in TSOT-23-6 package. Supply voltage range 10V to 30V. MSL rating 3 (168 hours) indicates moisture sensitivity constraint. Not recommended for new designs due to obsolete classification.

RT8458AGJ6 (Richtek USA Inc.): Active product status with ROHS3 compliance and MSL rating 3 (168 hours). Step-down topology with analog dimming in TSOT-23-6 package. Supply voltage range 17V to 31V with 47kHz switching frequency. Operating temperature range -40°C to 125°C (TJ) matches primary part specification. Suitable for designs accommodating higher supply voltage requirements and analog dimming control.

Frequently Asked Questions (FAQ)

Q: Can LT3799EMSE-1#PBF directly replace LM3445M/NOPB in existing PCB layouts?

A: No. LT3799EMSE-1#PBF uses 16-MSOP-EP packaging versus the 14-SOIC package of LM3445M/NOPB. Pin count, pitch, and physical dimensions differ, requiring PCB redesign. Flyback topology also requires different external component configurations compared to step-down topology.

Q: What is the primary difference between Triac and PWM dimming methods?

A: Triac dimming modulates the AC input voltage phase angle for brightness control. PWM dimming switches the DC output on and off at high frequency. MXHV9910BTR uses PWM dimming, which differs from the Triac dimming of LM3445M/NOPB and affects circuit design and dimming control implementation.

Q: Why is RT8402GJ6 listed as obsolete?

A: RT8402GJ6 product status is classified as obsolete by the manufacturer. Obsolete parts face discontinuation risk and reduced availability. New designs should prioritize active products: LT3799EMSE-1#PBF, MXHV9910BTR, or RT8458AGJ6.

Q: What does MSL rating 3 (168 hours) mean for RT8402GJ6 and RT8458AGJ6?

A: MSL (Moisture Sensitivity Level) 3 indicates the component absorbs moisture and requires controlled storage conditions. The 168-hour specification means the part must be used within 168 hours after exposure to ambient conditions above 30°C and 60% relative humidity, or it requires baking before reflow soldering. LM3445M/NOPB has MSL 1 (unlimited), requiring no moisture control.

Q: Can RT8458AGJ6 operate at the same supply voltage as LM3445M/NOPB?

A: No. RT8458AGJ6 requires minimum 17V supply voltage, while LM3445M/NOPB operates from 8V minimum. RT8458AGJ6 is suitable only for designs with higher supply voltage specifications (17V to 31V range).

Q: Is MXHV9910BTR suitable for lighting applications?

A: MXHV9910BTR is classified for signage applications in available data. While it functions as an AC DC offline switcher with PWM dimming, its primary application specification differs from LM3445M/NOPB lighting classification. Design validation is required for alternative application use.

Q: What are the thermal operating range differences between substitute parts?

A: LM3445M/NOPB, LT3799EMSE-1#PBF, and RT8458AGJ6 operate to 125°C (TJ). MXHV9910BTR and RT8402GJ6 operate to 85°C (TA). The 40°C difference affects thermal design margins and maximum ambient operating conditions.