Summary

The MIC3203/MIC3203-1 is a hysteretic step-down, constant-current, High-Brightness LED (HB LED) driver. It provides an ideal solution for interior/exterior lighting, architectural and ambient lighting, LED bulbs, and other general illumination applications. This board enables the evaluation of the MIC3203/MIC3203-1 for 1A LED current. The board is optimized for ease of testing, with all the components on a single side. The device operates from a 4.5V to 42V input voltage range, and controls an external power MOSFET to drive high current LEDs. When the input voltage approaches and crosses UVLO threshold, the internal 5V VCC is regulated and the external MOSFET is turned on if EN pin and DIM pin are high. The inductor current builds up linearly. When the CS pin voltage hits the VCS(MAX) with respect to VIN, the external MOSFET is turned off and the Schottky diode takes over and returns the current to VIN. Then the current through inductor and LEDs starts decreasing. When CS pin hits VCS(MIN), the external MOSFET is turned on and the cycle repeats.