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LM3421

ACTIVE

N-channel controllers for constant current LED drivers with series DIM FET driver

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TPS92691-Q1 ACTIVE Automotive multi-topology LED driver with rail-to-rail current sense amplifier Multi-topology capabilities with integrated N-channel FET.

Product details

Input voltage type DC/DC Topology Boost, Boost Controller, Buck-Boost, SEPIC Vin (min) (V) 4.5 Vin (max) (V) 75 Vout (max) (V) 72 Vout (min) (V) 3 Iout (max) (A) 5 Iq (typ) (mA) 2 Features Adjustable Switch Frequency, Enable/Shutdown, Thermal shutdown Operating temperature range (°C) -40 to 125 Dimming method Analog, PWM Number of channels 1 Rating Catalog
Input voltage type DC/DC Topology Boost, Boost Controller, Buck-Boost, SEPIC Vin (min) (V) 4.5 Vin (max) (V) 75 Vout (max) (V) 72 Vout (min) (V) 3 Iout (max) (A) 5 Iq (typ) (mA) 2 Features Adjustable Switch Frequency, Enable/Shutdown, Thermal shutdown Operating temperature range (°C) -40 to 125 Dimming method Analog, PWM Number of channels 1 Rating Catalog
HTSSOP (PWP) 16 32 mm² 5 x 6.4
  • VIN Range From 4.5 V to 75 V
  • High-Side Adjustable Current Sense
  • 2-Ω, 1-A Peak MOSFET Gate Driver
  • Input Undervoltage and Output Overvoltage Protection
  • PWM and Analog Dimming
  • Cycle-by-Cycle Current Limit
  • Programmable Switching Frequency
  • Zero Current Shutdown and Thermal Shutdown
  • LED Output Status Flag (LM3423 and LM3423-Q0 Only)
  • Fault Status Flag and Timer(LM3423 and LM3423-Q0 Only)
  • VIN Range From 4.5 V to 75 V
  • High-Side Adjustable Current Sense
  • 2-Ω, 1-A Peak MOSFET Gate Driver
  • Input Undervoltage and Output Overvoltage Protection
  • PWM and Analog Dimming
  • Cycle-by-Cycle Current Limit
  • Programmable Switching Frequency
  • Zero Current Shutdown and Thermal Shutdown
  • LED Output Status Flag (LM3423 and LM3423-Q0 Only)
  • Fault Status Flag and Timer(LM3423 and LM3423-Q0 Only)

The LM3421 and LM3423 family of devices are versatile high voltage N-channel MOSFET controllers for LED drivers. They can be easily configured in buck, boost, buck-boost and SEPIC topologies. This flexibility, along with an input voltage rating of 75 V, makes the these controllers ideal for illuminating LEDs in a large family of applications.

Adjustable high-side current sense voltage allows for tight regulation of the LED current with the highest efficiency possible. The LM3421 and LM3423 devices use predictive off-time (PRO) control, which is a combination of peak current-mode control and a predictive off-timer. This method of control eases the design of loop compensation while providing inherent input voltage feed-forward compensation.

The LM3421 and LM3423 devices include a high-voltage start-up regulator that operates over a wide input range of 4.5 V to 75 V. The internal PWM controller is designed for adjustable switching frequencies of up to 2 MHz, thus enabling compact solutions.

The LM3421 and LM3423 family of devices are versatile high voltage N-channel MOSFET controllers for LED drivers. They can be easily configured in buck, boost, buck-boost and SEPIC topologies. This flexibility, along with an input voltage rating of 75 V, makes the these controllers ideal for illuminating LEDs in a large family of applications.

Adjustable high-side current sense voltage allows for tight regulation of the LED current with the highest efficiency possible. The LM3421 and LM3423 devices use predictive off-time (PRO) control, which is a combination of peak current-mode control and a predictive off-timer. This method of control eases the design of loop compensation while providing inherent input voltage feed-forward compensation.

The LM3421 and LM3423 devices include a high-voltage start-up regulator that operates over a wide input range of 4.5 V to 75 V. The internal PWM controller is designed for adjustable switching frequencies of up to 2 MHz, thus enabling compact solutions.

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TPS92691 ACTIVE TPS92691 multi-topology LED driver with rail-to-rail current sense amplifier This product is a multi-topology low-side NFET LED controller with rail-to-rail current sense capability.

Technical documentation

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Type Title Date
* Data sheet LM342x N -Channel Controllers for Constant-Current LED Drivers datasheet (Rev. G) PDF | HTML 30 Jul 2019
Selection guide Power Management Guide 2018 (Rev. R) 25 Jun 2018
Technical article Driving LEDs: topology matters PDF | HTML 26 Feb 2016
Application note AN-1656 Design Challenges of Switching LED Drivers (Rev. A) 03 May 2013
EVM User's guide LM3421 SEPIC LED Driver Evaluation Board for Automotive Applications (Rev. B) 03 May 2013
EVM User's guide AN-1907 LM3423 Buck-Boost Configuration Evaluation Board (Rev. A) 01 May 2013
Application note AN-1982 Small, Wide Input Voltage Range LM2842 Keeps LEDs Cool (Rev. A) 23 Apr 2013

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

LM3423BBLSCSEV — LM3423 Buck-Boost 2-Layer Low Side Current Sense Evaluation Board

This wide range evaluation board showcases the LM3423 NFET controller used with a buck-boost current regulator. It is designed to drive 4 to 8 LEDs at a maximum average LED current of 700 mA from a DC input voltage of 10 to 70V.

The evaluation board showcases most features of the LM3423 including (...)

User guide: PDF
Not available on TI.com
Evaluation board

LM3423BS2LYEV — Boost 2 Layer LED Driver Evaluation Board

This evaluation board showcases the LM3423 NFET controller used with a boost current regulator. It is designed to drive 9 to 12 LEDs at a maximum average LED current of 700mA from a DC input voltage of 10 to 26V. The evaluation board showcases most features of the LM3423 including PWM dimming, (...)

User guide: PDF
Not available on TI.com
Simulation model

LM3421 PSpice Transient Model (Rev. B)

SNVMAB4B.ZIP (132 KB) - PSpice Model
Simulation model

LM3421 TINA-TI Startup Reference Design

SNVMAS0.TSC (891 KB) - TINA-TI Reference Design
Simulation model

LM3421 TINA-TI Steady Reference Design

SNVMAR9.TSC (895 KB) - TINA-TI Reference Design
Simulation model

LM3421 TINA-TI Transient Spice Model

SNVMAS1.ZIP (25 KB) - TINA-TI Spice Model
Simulation tool

PSPICE-FOR-TI — PSpice® for TI design and simulation tool

PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
Package Pins CAD symbols, footprints & 3D models
HTSSOP (PWP) 16 Ultra Librarian

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