The ADM8828/ADM8829 is a charge-pump voltage inverterwhich may be used to generate a negative supply from a positiveinput. Input voltages ranging from +1.5 V to +5.5 V can beinverted into a negative –1.5 V to –5.5 V output supply. Thisinverting scheme is ideal for generating a negative rail in singlepower-supply systems. Only two small external capacitors areneeded for the charge pump. Output currents up to 25 mA withgreater than 99% efficiency are achievable.