The MP3388S is a step-up converter with 8 current-source channels designed to drive arrays of white LED for LCD-panel backlighting applications. The MP3388S uses current-mode, fixed-frequency architecture, and users can select a switching frequency of either 625kHz or 1.25MHz. It generates an output voltage up to 50V from a 4.3V-to-25V input supply. The MP3388S independently regulates the current in each LED string set by an external current setting resistor to a user-programmed value. The MP3388S applies an internal current source to each LED string terminal, and can achieve a current balance of 2.5% regulation accuracy between strings. Its low 600mV regulation voltage on LED current sources reduces power loss and improves efficiency. The MP3388S features external PWM dimming or DC-input PWM dimming, which allows for flexible backlight luminance control. The dimming PWM signal can be generated internally, and the dimming frequency is programmed by an external setting capacitor.
The EV3388DR-01A is an evaluation board for the MP3388DR, a step-up converter designed for large liquid-crystal displays that employ an array of LEDs as the light source. It can drive up to 8 strings in parallel and 10 LEDs per string.
The MP3388 uses internal switch current mode, fixed frequency architecture and includes current ballast in each string terminal, which achieves ±3% current regulation accuracy between strings. Low feedback voltage at each LED string help reduce power loss and improve efficiency.
The MP3388 has multiple features to protect the converter from fault conditions, including under-voltage lockout, current limiting, over voltage, short LED, open LED and thermal shut-down protection.
The MP3388 is available in small QFN24 (4mmx 4mm), TSSOP28 and SOIC28 package.