| 摘要 |
The invention relates to a switch-mode power supply comprising an input circuit (1) for periodically switching an input voltage (Ue) or an input current (Ie) on and off with a switching frequency (fS), a transmission circuit (2) connected thereto, and an output circuit (3), which is connected to the latter and to which a load (4) can be connected. In order to provide a switch-mode power supply which has a smaller size and lower costs, compared with conventional switch-mode power supplies, it is provided that the transmission circuit (2) is formed by a bandpass filter (7), which is constructed from at least one capacitance (C) and at least one inductance (L) and whose resonant frequency (f0) lies outside, in particular above, the switching frequency (fS) of the input circuit (1). By omitting the transformer that is usually used, it is possible to avoid the disadvantages of said transformer. In order to obtain DC isolation, it is provided that, in each branch of the LC bandpass filter (7) at least one capacitor (C) is provided in series with the rest of the circuitry. |
