TI Delivers Small Linear LED Driver for Portable Electronics

Texas Instruments Inc. (TI) introduced what the company claims is the smallest two-bank, low dropout (LDO) regulator to support light emitting diode (LED) lighting in portable applications, such as mobile phones, navigation systems, MP3 and media players. The device enables quality color backlighting from a tiny 1.2 mm x 1.2 mm package, allowing end–users to experience blinking and dimming of color keypads and navigation pad lights.

TI's TPS75105 linear, quad-LDO with matching LED constant current source drives up to four LEDs in two banks with each LED at 25mA (max). Each bank features independent pulse width modulation (PWM) brightness control that controls the dimming level from "full brightness" to "off."

Among the device's key features are: regulated output current with 2% LED-to-LED matching; 28mV typical dropout voltage extends usable supply range in Li-Ion battery applications; no internal switching signals, eliminating electromagnetic interface (EMI); over-current and over-temperature protection; and default LED current eliminates external components.

The TPS75105 LED driver, as well as a TPS75103 version that supports 3-mA, are available today in volume production from TI and its worldwide network of distributors. Both LED drivers come in an ultra-small, 9-ball, 0.4 mm ball-pitch wafer chip-scale package (WCSP). Suggested resale price starts at $0.65 in 1,000-unit quantities.