| 摘要 |
<p>PURPOSE:To ensure the protection and detection against layer short-circuit by adopting the constitution such that a voltage application to a low voltage coil is interrupted when a pulse voltage of the low voltage coil of a flyback transformer exceeds a reference value. CONSTITUTION:If a layer short-circuit takes place in a high voltage coil 2, an AC current flowing to the low voltage coil 3 is increased and then the pulse voltage in the low voltage coil 3 is increased. A layer short-circuit detection circuit 28 gives an output when the said pulse voltage exceeds a reference value and the detected output signal is fed to a gate circuit 30. The gate circuit 30 uses the detection signal to open a gate and to give a melting current to a fuse 31, which is blown out thereby preventing application of voltage to the low voltage coil 31 of the flyback transformer 1. Thus, the detection of layer short-circuit and the safety to layer short-circuit are ensured.</p> |
