illustrate

The TPS60231 charge pump is optimized to display white LED supplies for color backlight applications. The device provides each LED with an initial value that can be set with a constant current through an external resistor. The supply voltage range is 2.7 V to 6.5 V and is ideal for all applications powered by a single Li-ion battery or three to four NiCm, NiMH or alkaline batteries. With input voltages ranging from 3.1 V to 6.5 V, the device delivers high output currents up to 25 and 75 mA total LED mA. High efficiency is combined by utilizing a 1x/1.5x fractional conversion technique using a current source with very low dropout voltage. In addition, a current-controlled charge pump ensures low input current ripple and EMI.

characteristic

• Regulated Output Current Matched to 0.4%
• Drive up to 3 LEDs at 25 mA each
• LED brightness control of the signal via PWM
• High efficiency, conversion rate with 1x and 1.5x mode
• 1 MHz switching frequency
• 2.7 V to 6.5 V operating voltage range input
• Internal soft-start limits inrush current
• Low input ripple and low EMI
• Overcurrent and overtemperature protection
• Undervoltage lockout
• Ultra-small 3mm x 3mm QFN package
• apply
  • White LED backlights are used in cellular phones, smartphones, PDAs, handheld computers, digital cameras, color displays, and camcorders
  • Keyboard backlight