| 摘要 |
<p>An a.c. to low voltage d.c. converter comprises a pair of input voltage supply lines (Vin,OV) and a semiconductor switch element (T1) and a capacitor (C1) connected in series between the supply lines. An output (Vo) for d.c. voltage is provided across the capacitor (C1). A sensing circuit (10) is responsive to the input voltage and is arranged to trigger the switching element (T1) to conduct only during a portion of the a.c. voltage below a predetermined voltage.</p> |
