Fuente Conmutada

Switched-mode power supply

A switched-mode power supply (switching-mode power supply, SMPS, or switcher) is an electronic power supply[->0] that incorporates a switching regulator to convert electrical power efficiently. Like other power supplies, an SMPS transfers power from a source, like mains power[->1], to a load, such as a personal computer[->2], while converting voltage[->3] andcurrent[->4] characteristics. An SMPS is usually employed to efficiently provide a regulated output voltage, typically at a level different from the input voltage.
Unlike a linear power supply[->5], the pass transistor of a switching-mode supply continually switches between low-dissipation[->6], full-on and full-off states, and spends very little time in the high dissipation transitions (which minimizeswasted energy). Ideally, a switched-mode power supply dissipates no power. Voltage regulation[->7] is achieved by varying the ratio of on-to-off time. In contrast, a linear power supply regulates the output voltage by continually dissipating power in the pass transistor[->8]. This higher power conversion efficiency is an important advantage of a switched-mode power supply. Switched-mode powersupplies may also be substantially smaller and lighter than a linear supply due to the smaller transformer size and weight.
Switching regulators are used as replacements for the linear regulators when higher efficiency, smaller size or lighter weight are required. They are, however, more complicated, their switching currents can cause electrical noise problems if not carefully suppressed, and simpledesigns may have a poor power factor[->9].

History
1926: "Electrical condensors" by Coursey[1] mentions high frequency weldingHYPERLINK \l "cite_note-1"[2][->10] and furnaces.[1]
1959: Transistor oscillation and rectifying converter power supply system U.S. Patent 3,040,271[->11] is filed.[3]
1970: High-Efficiency Power Supply produced from about 1970 to 1995.[4]HYPERLINK \l"cite_note-4"[5]HYPERLINK \l "cite_note-5"[6]HYPERLINK \l "cite_note-6"[7]
1972: HP-35[->12], Hewlett-Packard's first pocket calculator, is introduced with transistor switching power supply for light-emitting diodes[->13], clocks, timing, ROM[->14], and registers.[8]
1976: "Switched mode power supply" U.S. Patent 4,097,773[->15] is filed.[9]
1977: Apple II[->16] is designed with a switching mode powersupply. "For its time (1977) it was a breakthrough, since until then switching mode power supplies weren’t used. Designed by Rod Holt,".[10] "Rod Holt was brought in as product engineer and there were several flaws in Apple II that were never publicized. One thing Holt has to his credit is that he created the switching power supply that allowed us to do a very lightweight computer".[11]
1980: TheHP8662A 10 kHz – 1.28 GHz synthesized signal generator[->17] went with a switched power supply.[12




Cambiar-modo de suministro de energía

Una fuente de alimentación de modo conmutado (conmutación de modo de fuente de alimentación, SMPS, o conmutador) es una fuente de alimentación electrónica que incorpora un regulador de conmutación para convertir energía eléctrica de manera eficiente. Aligual que otras fuentes de alimentación, un SMPS transferencias de energía desde una fuente, como alimentación de red, a una carga, tal como un ordenador personal, mientras que la conversión de las características de tensión y corriente. Un SMPS se emplea generalmente para proporcionar eficientemente una tensión de salida regulada, típicamente a un nivel diferente de la tensión de entrada.
Adiferencia de una fuente de alimentación lineal, el transistor de paso de una fuente de alimentación conmutada en modo pasa continuamente entre los de baja disipación, lleno-en total y los estados-off, y pasa muy poco tiempo en las transiciones de alta disipación (lo que minimiza el desperdicio de energía). Idealmente, una fuente de alimentación de modo conmutado se disipa ninguna energía. La...