The LM3401EVAL is an evaluation board for LM3401, a switching buck regulator derived current source designed to drive a series string of high power, high brightness LEDs. The LM3401 controls an external PFET, allowing the user to select a power device for the desired level of forward LED current. The LM3401 evaluation board can supply continuous current as high as 1A. It is designed to operate at ambient temperatures up to 75°C. The LM3401 maintains constant current through any number of series connected LEDs as long as the input voltage is greater than the combined forward voltage of the LED string. The LM3401 evaluation board includes an input terminal for a digital dimming signal, which is compatible with PWM dimming frequencies up to 10kHz.