A low on-resistance MOSFET and headroom voltage are provided to improve efficiency. The MP3364 has a standard I2C digital interface for easy use. The switching frequency can be configured via a resistor, I2C interface, or external clock. The MP3364 provides analog, PWM, and mixed dimming modes with a PWM input. The dimming mode can be selected via the I2C interface or the MIX/AD pin. The device also has a phase shift function to eliminate noise during PWM dimming.