The MCP1664 device is a compact, space-efficient, fixed-frequency, non-synchronous step-up converter optimized to drive LED strings with constant current from two and three-cell alkaline and NiMH/NiCd or one-cell Li-Ion or Li-Polymer batteries. The device integrates a 36V, 400 mΩ low-side switch, which is protected by the 1.8A cycle-by-cycle inductor peak current limit operation. Low-voltage technology allows the MCP1664 to start-up without high inrush current or output overshoot. All compensation and protection circuitry is integrated to minimize the number of external components.