| 摘要 |
<p>A switched mode AC-DC converter (rectifier) uses a resonant LLC stage as its front end. The switching converter comprises a primary side including an AC source 101, first and second switches 104, 106, and a resonant LLC circuit which includes the primary winding 118 of the transformer. The resonant LLC circuit may also include a second inductor 116 and a capacitor 114. Alternatively the second inductor may be provided by leakage inductance within the transformer. A secondary side of the converter includes a secondary winding 120 of the transformer and a rectifying arrangement. The rectifying arrangement may comprise two series connected diodes 122, 124 and two series connected capacitors 126, 128. A buck or boost DC-DC converter may be provided to accept the rectified DC voltage and provide a DC output. A hold-up circuit comprising a capacitor may be provided for holding up the output voltage. The switching converter may have a first mode of operation where the switching frequency is confined to a first range, and a second mode of operation where the switching frequency is confined to a second range.</p> |
