The LM2756 is a highly integrated, switched-capacitor, multi-display LED driver that can drive up to 8 LEDs in parallel with a total output current of 180mA. Regulated internal current sources deliver excellent current and brightness matching in all LEDs. The LED driver current sinks are split into three independently controlled groups. The primary group (Group A) can be configured to drive four, five or six LEDs for use in the main phone display, while the secondary group (Group B) can be configured to drive one, two or three LEDs for driving secondary displays, keypads and/or indicator LEDs. An additional driver, D1C, is provided for additional indicator lighting functions. The device provides excellent efficiency without the use of an inductor by operating the charge pump in a gain of 3/2 or in Pass-Mode. The proper gain for maintaining current regulation is chosen, based on LED forward voltage, so that efficiency is maximized over the input voltage range. The LM2756 is available in National’s tiny 20-bump, 0.4mm pitch, thin micro SMD package.
The LM2756 is a highly integrated, switched‑capacitor LED driver that can drive up to eight LEDs with up to 30 mA per diode and a total output current of 180 mA. It offers 32 exponential dimming steps with an 800:1 dimming ratio and includes programmable auto‑dimming, I²C‑compatible control, and a low‑profile 20‑bump micro‑SMD package.
The document lists absolute maximum ratings, electrical characteristics, pin functions, package marking details, and typical performance curves such as LED drive efficiency, input current versus voltage, and quiescent/shutdown currents. Ordering information and application notes for dual‑display LCD backlighting and indicator lighting are also provided.
| Number of LEDs driven | Up to 8 LEDs |
|---|---|
| Maximum LED current per diode | 30 mA |
| Total output current | 180 mA |
| Dimming steps | 32 exponential steps (800:1 ratio) |
| Package type and size | 20‑bump micro SMD, 1.615 mm × 2.015 mm × 0.6 mm |
| Switching frequency | 1.0 MHz to 1.6 MHz |
| Shutdown supply current | 3.7 pA to 5.5 pA |
It can drive up to eight LEDs, arranged in three independently controlled groups.
The device can supply a total output current of 180 mA, which can be split among the three groups.
The LM2756 is offered in a 20‑bump micro SMD package measuring 1.615 mm × 2.015 mm × 0.6 mm.