Dual Output Boost Drives up to 6 White LEDs & an OLED Display from a 2mm × 3mm DFN Package

Jun 13 2007 - MILPITAS, CA
  • Linear Technology announces the LT3498, a dual output boost converter featuring a 2.3MHz PWM LED driver and a low noise OLED driver. The device includes an internal power switch and Schottky diode for each channel, all in 2mm × 3mm DFN package. The LT3498's wide 2.5V to 12V input voltage range enables it to operate from single cell Li-Ion batteries up to fixed 12V input rails, delivering outputs up to 32V. Each of the converters can be independently dimmed or shut down. From a single cell Li-Ion input, the LED driver channel can drive up to six series 20mA white LEDs while the OLED driver can deliver up to 24mA to a 16V output. This highly integrated power solution is ideal for dual display electronic devices.

    The LT3498's LED driver uses a 2.3MHz PWM frequency, keeping switching noise out of critical wireless and audio bands. The device also uses a high side current sense topology, providing a one-wire current source for the LED Driver. Similarly, the OLED driver uses a unique control scheme that delivers both high efficiency and low output ripple over a wide load current range. This technique guarantees that the switching frequency stays above the audio band for the entire load range, making it ideal for noise-sensitive applications such as MP3 players and cellular phones. Additional features include open LED protection and OLED output disconnect.

    The LT3498EDDB is available from stock in a 12-lead 2mm × 3mm DFN package. Pricing starts at $1.95 each for 1,000-piece quantities.

    Summary of Features: LT3498

    • Dual Output Boost for Dual Display Devices
    • Drives Up to Six White LEDs & OLED/LCD Bias
    • Internal Power Switches and Schottky Diodes
    • Independent Dimming & Shutdown
    • 200mV High Side Sense on LED Driver Allows "One-Wire Current Source"
    • Wide Input Voltage Range: 2.5V to 12V
    • Wide Output Voltage Range: Up to 32V
    • 2.3MHz PWM Frequency for LED Driver
    • PFM for OLED Driver is Non-Audible over Entire Load Range
    • Open LED Protection
    • OLED Output Disconnect
    • Available in 12-Pin 2mm × 3mm DFN Package

    Dual Output Boost Drives up to 6 White LEDs & an OLED


    Download PDF version

  • Editor's Contact Information
Stay Informed