| 摘要 |
PURPOSE:To secure the switching behavior safely and accurately by controlling the zero term of a current so as to keep a mean value of output voltage from fluctuation at switching. CONSTITUTION:When a positive output current becomes almost zero, an output 1 of a microcurrent detection circuit 7 changes from ''1'' to ''0'' and an output 2 changes from ''0'' to ''1''. In this case, elements U1 and Y1 of a positive side bridge 3A are kept on. In accordance as the output 2 of the microcurrent detection circuit 7 changes from ''0'' to ''1'', an AND circuit 10 issues a signal ''1'' to turn one input of an AND gate on the left side of AND/OR circuits 19-24 to ''1'', however, output V20 of the AND/OR circuit 20 and output V20of the AND/OR circuit 22 are turned to ''1'', and ignition commands V20, X20 are given to elements V2, X2 of a negative- phase bridge 3B. |
