LTC3202 Low Noise, High Efficiency Charge Pump for White LEDs

Product Details

The LTC3202 is a low noise, constant frequency charge pump DC/DC converter that uses fractional conversion to increase efficiency in white LED applications. The part can be used to produce a regulated voltage or current of up to 125mA from a 2.7V to 4.5V input. Low external parts count (two flying capacitors and two small bypass capacitors at VIN and VOUT) make the LTC3202 ideally suited for small, battery-powered applications.

An internal 2-bit DAC allows LED current to be adjusted for LED brightness control. The LTC3202 also has thermal shutdown protection and can survive a continuous short-circuit from VOUT to GND. Built-in soft-start circuitry prevents excessive inrush current during start-up. High switching frequency enables the use of small external capacitors. A low current shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1µA.

The LTC3202 is available in the 10-pin MSOP and 3mm x 3mm DFN packages.

Applications

  • White LED Backlighting
  • Programmable Boost Current Source


Features and Benefits

  • Low Noise Constant Frequency Operation
  • 25% Less Input Current Than Doubler Charge Pump
  • High Output Current: Up To 125mA
  • Small Application Circuit
  • Regulated Output Voltage or Current
  • Automatic Soft-Start
  • VIN Range: 2.7V to 4.5V
  • No Inductors
  • 1.5MHz Switching Frequency
  • ICC < 1µA in Shutdown
  • Available in 10-Pin MSOP and 3mm x 3mm DFN Packages