LT3491 - White LED Driver in SC70 with Integrated Schottky
- Drives Up to Six White LEDs from a 3V Supply
- High Side Sense Allows “One Wire Current Source”
- Internal Schottky Diode
- One Pin Dimming and Shutdown
- 27V Open LED Protection
- 2.3MHz Switching Frequency
- ±5% Reference Accuracy
- VIN Range: 2.5V to 12V
- Requires Only 1µF Output Capacitor
- Wide 300:1 True Color PWMTM Dimming Range
- 8-Lead SC70 Package
- Low Profile 6-Lead DFN Package (2mm × 2mm × 0.75mm)
The LT3491 is a fixed frequency step-up DC/DC converter specifically designed to drive up to six white LEDs in series from a Li-Ion cell. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The device features a unique high side LED current sense that enables the part to function as a “one wire current source;” one side of the LED string can be returned to ground anywhere, allowing a simpler one wire LED connection. Traditional LED drivers use a grounded resistor to sense LED current, requiring a 2-wire connection to the LED string.
The 2.3MHz switching frequency allows the use of tiny inductors and capacitors. A single pin performs both shutdown and accurate LED dimming control. Few external components are needed: open-LED protection and the Schottky diode are all contained inside the tiny SC70 package. With such a high level of integration, the LT3491 provides a high efficiency LED driver solution in the smallest of spaces.
CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.
For complete and up to date package information and drawings, please refer to our packaging page
- Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
- Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
- Please refer to our general ordering information or the product datasheet for more details
Package Variations and Pricing
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|DC905A||LT3491ESC8 Demo Board||$75.00|
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