MP3367 Step-Up Converters

The MP3367 from Monolithic Power Systems (MPS) is a step-up converter with six-channel current sources, designed to drive white LED arrays as backlighting in small-to-mid-size LCD panels. The device uses peak current mode as its PWM control architecture to regulate the boost converter. Six-channel current sources are applied to the LED cathode to adjust the LED brightness. The MP3367 regulates the current in each LED string to the value set by an external current-setting resistor, with 2.5% current regulation accuracy between strings. The IC employs a low on-resistor MOSFET and a low headroom voltage, designed for higher efficiency. It has a standard I²C digital interface for ease of use. The switching frequency can be programmed by a resistor, I²C interface, or external clock. The MP3367 provides analog, PWM, and mix dimming mode with a PWM input. Dimming mode can be selected with the I²C interface or the MIX/AD pin. It also has a phase shift function to eliminate noise during PWM dimming. Robust protections are included to guarantee the safe operation of the device. Protection modes include overcurrent protection (OCP), overvoltage protection (OVP), overtemperature protection (OTP), LED short, and open protection. There is also an option that automatically decreases the LED current at higher temperatures. The MP3367 is available in QFN-24 4 mm x 4 mm and TSSOP28-EP packages.