Buck regulator forms high-power, inverting -5V supply

摘要

Configuring a step-down switching-converter IC as an inverter yields an efficient, high-power, -5V supply that can of deliver currents as high as 4.5 A at the 12V input or 3.2A at the 5V input (Figure 1). Conventional inverting power supplies do their switching using a p-channel MOSFET (Figure 2). That configuration works well at lower currents, but has limited use above approximately 2A, depending on the input and output voltage levels and the MOSFET you use.