LT3955

PRODUCTION

60VIN LED Converter with Internal PWM Generator

Data Sheet Product Selection Table
Viewing:

Overview

  • 3000:1 True Color PWM™ Dimming for LEDs
  • Wide VIN Range: 4.5V to 60V
  • Rail-to-Rail Current Sense Range: 0V to 80V
  • Internal 80V/3.5A Switch
  • Programmable PWM Dimming Signal Generator
  • Constant Current (±3%) and Constant-Voltage (±2%) Regulation
  • Accurate Analog Dimming
  • Drives LEDs in Boost, SEPIC, CUK, Buck Mode, Buck-Boost Mode, or Flyback Configuration
  • Output Short-Circuit Protected Boost
  • Open LED Protection and Reporting
  • Adjustable Switching Frequency: 100kHz to 1MHz
  • Programmable VIN UVLO with Hysteresis
  • C/10 Indication for Battery Chargers
  • Low Shutdown Current: <1μA
  • Thermally Enhanced 5mm × 6mm QFN Package

The LT3955 is a DC/DC converter designed to operate as a constant-current source and constant-voltage regulator. It features an internal low side N-channel MOSFET rated for 80V/3.5A. The LT3955 is ideally suited for driving high current LEDs, but also has features to make it suitable for charging batteries and supercapacitors. The fixed frequency, current mode architecture results in stable operation over a wide range of supply and output voltages. A voltage feedback pin serves as the input for several LED protection features, and also makes it possible for the converter to operate as a constant-voltage source. A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance or external component size.

The LT3955 senses output current at the high side or at the low side of the load. The PWM input can be configured to self-oscillate at fixed frequency with duty ratio programmable from 4% to 96%. When driven by an external signal, the PWM input provides LED dimming ratios of up to 3000:1. The CTRL input provides additional analog dimming capability.

Applications

  • High Power LEDs
  • Output Short-Circuit Protected Boost
  • Battery and SuperCap Chargers
  • Accurate Current Limited Voltage Regulators
LT3955
60VIN LED Converter with Internal PWM Generator
94% Efficiency 20W Boost LED Driver with Internal PWM Dimming PWM Dimming Waveforms at Various DIM Voltage Settings Product Package 1
Add to myAnalog

Add product to the Products section of myAnalog (to receive notifications), to an existing project or to a new project.

Create New Project
Ask a Question

Documentation

Data Sheet 1

Reliability Data 1

User Guide 1

Data Sheet

This is the most up-to-date revision of the Data Sheet.

Learn More
Add to myAnalog

Add media to the Resources section of myAnalog, to an existing project or to a new project.

Create New Project

Software Resources

Can't find the software or driver you need?

Request a Driver/Software

Hardware Ecosystem

Parts Product Life Cycle Description
Protection Switches & Controllers 2
LT4363
RECOMMENDED FOR NEW DESIGNS High Voltage Surge Stopper with Current Limit
LT4320
LT4320-1
Ideal Diode Bridge Controller
Modal heading
Add to myAnalog

Add product to the Products section of myAnalog (to receive notifications), to an existing project or to a new project.

Create New Project

Tools & Simulations

LTspice 1

Models for the following parts are available in LTspice:

  • LT3955
LTspice

LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

Evaluation Kits

eval board
schematic 1
schematic 2
schematic 3
schematic 4
schematic 5
DC2020A

LT3955EUHE Demo Board | Boost LED Driver; 5V to 60VIN, VOUT up to 67V @ 0.3A

Buy Now View Details

Product Details

Demonstration circuit 2020A is a 60VIN, 80VOUT LED driver. It generates its own PWMOUT waveform from its internal PWM generator for accurate PWM dimming with up to 33:1 brightness ratio. It accepts an input voltage from 5V to 60V and drives up to 67V of LEDs at 300mA (when PVIN is less than VLED). DC2020A features both PWM and analog dimming of the LED string. It has an OPENLED flag that indicates when the LED string has been removed. DC2020A features high efficiency at 350kHz switching frequency. At high LED string voltages up to 67V and 300mA of LED current, the single switch controller has 92% efficiency. The LT3955 has an internal 80V, 3.5A switch that simplifies the schematic and layout.
DC2020A
LT3955EUHE Demo Board | Boost LED Driver; 5V to 60VIN, VOUT up to 67V @ 0.3A
DC2020 Demo Board DC2020 Demo Board DC2020 Demo Board DC2020 Demo Board DC2020A - Schematic

Latest Discussions

6 Years Ago
LT3955
View related discussion on EngineerZone®

Recently Viewed