Overview
Features and Benefits
- True Color PWM™ Dimming Delivers Up to 3000:1 Dimming Ratio
- Drives Six Strings of LEDs at Up to 30mA
- ±1.5% Accurate LED Current Matching
- Wide Input Voltage Range: 3.2V to 30V
- Output Voltage Up to 44V
- Regulates Current Even When VIN > VOUT
- Disconnects LEDs in Shutdown
- Programmable Open LED Protection (Regulated)
- OPENLED Alert Pin
- Programmable LED Current Derating
- Adjustable Frequency: 200kHz to 2.5MHz
- Synchronizable to an External Clock
- Parallel Channels for Higher Current per LED String
- Thermally Enhanced 4mm × 4mm QFN and 24-Lead TSSOP Packages
Product Details
The LT3598 is a fixed frequency step-up DC/DC converter designed to drive up to six strings of LEDs at an output voltage up to 44V. LED dimming can be achieved with analog dimming on the CTRL pin, and with pulse width modulation dimming on the PWM pin. The LT3598 accurately regulates LED current even when the input voltage is higher than the LED output voltage. The switching frequency is programmable from 200kHz to 2.5MHz through an external resistor.
Additional features include programmable overvoltage protection, switching frequency synchronization to an external clock, LED current derating based on junction temperature and/or LED temperature, LED string disable control, OPENLED alert pin and output voltage limiting when all LED strings are disconnected. The LT3598 is available in a thermally enhanced 24-lead (4mm × 4mm) QFN and 24-lead TSSOP packages.
Applications
- Notebook Computer Display
- Medium Size Displays
- Automotive LCD Display
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
Documentation
Reliability Data (1)
Evaluation Kit Manuals (1)
Tools & Simulations
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.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.

Models for the following parts are available in LTspice:
Reference Materials
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Support & Discussions
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.