| 摘要 |
<p>The supply voltage low voltage auxiliary circuits is derived from the higher voltage main supply batteries through a DC-DC converter comprising an oscillator driving a step down transformer which feeds an outputrectifier. The oscillator has two power transistors (9,10) operating in push-pull mode into the centre tapped (8) primary (1) of the step down transformer (4). The bases of the push-pull pair are driven through diodes (17) from the collectors of a long tailed pair phase splitter circuit (11). The long tailed pair (11) has the emitters connected to a start up circuit (18). A tertiary winding (3) on the step down transfer provides feedback to sustain the operation of the push-pull oscillator. The secondary winding feeds a rectifier (5) giving a DC voltage at the output terminals (6,7).</p> |
