TEXAS Instruments has released an organic light emitting diode (OLED) display power conversion integrated circuit (IC) and a white LED charge pump for backlight applications.
The TPS65130 is a dual-output dc/dc converter, optimised to generate a positive output voltage up to 15V and a negative output voltage down to -12V with programmable sequencing. The driver has a power conversion efficiency of up to 89%.
It supports OLED and charge-coupled device (CCD) sensor bias supply applications in battery-powered equipment such as mobile phones, PDAs, digital cameras, and camcorders. The unit supports an input voltage range of 2.7V to 5.5V. This allows it to be powered directly from a single-cell lithium-ion (Li-Ion) battery or multi-cell nickel-metal hydride (NiMH), nickel-cadmium (NiCd), and alkaline batteries.
The TPS65130 has a 4mm x 4mm QFN package and a minimum number of external components. It operates at a low quiescent current with a fixed frequency pulse width modulation of 1.25MHz (minimum). This allows the use of 4.7μH inductors. Independent enable pins allow power-up and power-down sequencing for both outputs. Load-disconnect during shutdown conserves battery life.
The TPS60230 white LED charge pump manages the power supplied to white LED colour display backlight applications without the need for an inductor. The 87%-efficient 3mm x 3mm device can drive up to five white LEDs with a constant current of 25mA each, providing a total of 125mA. The 1MHz switching frequency allows the use of small capacitors (<1μF). The brightness level of each LED is adjusted through PWM dimming functions on two enable inputs.