Many portable devices use LCD displays. These displays need large positive and negative power supplies, but most mobile devices have power rails at 5 V, 3.3 V or even lower. Thus, the challenge is not ...

Combining the operation of a boost regulator and a negative voltage converter can generate a negative supply from a single low voltage supply. The circuit in Figure 5 shows a standard application ...

Audio amplifiers for high-power portable speakers such as trolley speakers usually operate with lithium-ion batteries, and these batteries can vary from a single cell to a few cells in series.