The TPS60230 charge pump is optimized for white LED supplies in backlit color display applications. The device provides a constant current, set by an external resistor, for each LED. The supply voltage ranges from 2.7 V to 6.5 V and is ideally suited for all applications powered by a single LI-Ion battery cell or three to four NiCd, NiMH, or Alkaline battery cells. The TPS60230 provides up to 25 mA per LED, for a total of 125 mA, for input voltages ranging from 3.1 V to 6.5 V. High efficiency is achieved by utilizing a 1x/1.5x fractional conversion technique in combi- nation with very low dropout current sources. Additionally, the current controlled charge pump ensures low input current ripple and EMI. Only two external 1 µF and two 0.47 µF capacitors are required to build a complete small and low cost power supply solution. The TP60230 switches at 1 MHz operating frequency and is available in a small 16-pin QFN (RGT) package to keep board space to a minimum.

• Regulated Output Current With 0.3% Matching Over Temperature
• Drives up to 5 LEDs at 25 mA Each
• LED Brightness Control Through PWM Control Signal
• High Efficiency by Fractional Conversion With 1x and 1.5x Modes
• 1 MHz Switching Frequency
• 2.7 V to 6.5 V Operating Input Voltage Range
• Internal Softstart Limits Inrush Current
• Low Input Ripple and Low EMI
• Overcurrent and Overtemperature Protected
• Undervoltage Lockout With Hysteresis
• Ultra-Small 3mm × 3mm QFN Package
• APPLICATIONS
  • White LED Backlight for Color Displays in Cellular Phones, Smart Phones, PDAs, Handheld PCs, Digital Cameras, and Camcorders
  • Key Backlight