Features and Benefits
- True Color PWM™ Dimming Ratio Up to 3000:1
- Drives Four Strings of LEDs at Up to 120mA
- ±1.5% Accurate LED Current Matching
- Wide Input Voltage Range: 3.1V to 30V
- Output Voltage Up to 44V
- Regulates LED Current Even When VIN > VOUT
- Disconnects LEDs in Shutdown
- Programmable Maximum VOUT (Regulated)
- Open/Short LED Protection and Fault Flags
- Programmable LED Current Derating
- Adjustable Frequency: 200kHz to 2.1MHz
- Synchronizable to an External Clock
- Analog Dimming Up to 20:1
- Programmable Input UVLO with Hysteresis
- Thermally Enhanced 32-Pin (5mm × 5mm) QFN and 28-Pin TSSOP Packages
The LT3599 is a fixed frequency 2A step-up DC/DC converter designed to drive four strings of 120mA LEDs up to a 44V output voltage. The switching frequency is programmable from 200kHz to 2.1MHz through an external resistor.
LED dimming can be achieved with analog dimming on the CTRL pin, and with pulse width modulation dimming on the PWM pin. The LT3599 accurately regulates LED current even when the input voltage is higher than the LED output voltage.
Additional features include programmable LED current derating, switching frequency synchronization to an external clock, LED string disable control, OPENLED alert pin, SHORTLED alert pins and programmable maximum output voltage when all LED strings are disconnected. The LT3599 is available in the thermally enhanced 32-pin (5mm × 5mm) QFN and 28-pin TSSOP packages.
- Automotive Navigation TFT LCD Displays
- Desktop and Notebook TFT LCD Displays
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 1327B is a 4-Channel 80mA LED Driver with +/-1.5% Current Matching featuring the LT3599. The LT3599 is a step-up DC/DC converter designed to drive up to 4-strings of LEDs at up to 120mA per string, and with an output voltage up to 44V. The LED strings are connected to internal current sources where the current level is set with an external resistor. Each string can have up to 10 white LEDs. Paralleling of strings is allowed.
The LT3599 runs from a 3.1V to 5.5V power supply, and the step-up converter is powered from an 8V to 16 voltage supply, though higher voltages up to 40V may be acceptable depending on the circuit requirements.
Tools & Simulations
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:
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.
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.