为应用程序选择正确的调节器

　　为应用程序选择正确的调节器

　　今天的系统板与各种电源调节器一起激增。在实际应用中，有三种不同类型的电压调节器：线性、开关和电荷泵。虽然射频电路可能需要具有最小噪声和rf发射的线性电源调节器，但处理器可能需要具有优良调节特性的高效率、高密度开关DC-DC转换器。和一个没有调节电荷泵可能足以驱动一系列¹车载LED。

　　更重要的是，线性稳压器只能产生低于电源电压的电压，而多功能开关稳压器可以升压（降压）、降压（降压）或反转（改变输入电源电压的极性）。同样，电荷泵执行升压，降压和反向输入电压，但具有有限的输出电流能力。

　　Linear choices

　　As a result of these characteristics， linear regulators are recommended when the voltage of the source powering the regulator is near the regulator’s output voltage and the circuit being powered does not care about the efficiency of the regulator， but requires very low noise specifications. In the last several years， however， these devices have been further improved in noise as well as in efficiency performance， while their input voltage handling capability has been enhanced and they now feature a wider operating temperature range. Among key suppliers pushing the performance envelope of linear regulators are Exar， Linear Technology， Maxim， Micrel， ON Semiconductor， and Texas Instruments.