Clocked power supply circuit with earth short protection has earth short detector, evaluation and switch regulator electronics that interwork to block switching transistor if short detected

摘要

The circuit has an input, output, earth short detection device and a first switching transistor (T2) clocked by switch regulating electronics in normal operation. If the first transistor is blocked a first output of the power supply circuit is electrically isolated from the input. The earth short detector (L4.1-L4.3), evaluation electronics and switch regulator electronics interwork so that when an earth short is detected in the power supply circuit or load (R2) the first switching transistor is blocked.