LM3429

LM3429 N-Channel Controller for Constant Current LED Drivers www.DataSheet4U.com PRELIMINARY LM3429 April 30, 2009 N-Channel Controller for Constant Current LED Drivers General Description The LM3429 is a versatile high voltage LED driver controller. With the capability to be configured in a Buck, Boost, BuckBoost (Flyback), or SEPIC topology, and an input and output operating voltage rating of 75V, the LM3429 is ideal for illuminating LEDs in a very diverse, large family of applications. Adjustable high-side current sense with a typical sense voltage of 100 mV allows for tight regulation of the LED current with the highest efficiency possible. Output LED current regulation is based on peak current-mode control with predictive Off-Time Control. This method of control eases the design of loop compensation while providing inherent input voltage feed-forward compensation. The LM3429 includes a high-voltage startup regulator that operates over a wide input range of 4.5V to 75V. The internal PWM controller is designed for adjustable switching frequencies of up to 2.0MHz, thus enabling compact solutions. Additional features include: precision reference, logic compatible DIM input suitable for fast PWM dimming, cycle-by-cycle current limit, and thermal shutdown. The LM3429 comes in a low profile, thermally efficient TSSOP EP 14-lead package. Features ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ VIN range from 4.5V to 75V 2% Internal reference voltage (1.235V) Current sense voltage adjustable fro...