Patent ID: 7233085
Filing Date: 2007-06-19
Classification: H02M,H04N,Y02B

Abstract:
1. A protection circuit with a first switching stage for monitoring output voltages of a power supply unit which has a normal mode and a standby mode, said power supply unit being a switched-mode power supply with an isolating transformer and a primary side and a secondary side, and said protection circuit being arranged at said secondary side, wherein said first switching stage comprises a current input, to which output voltages are coupled for monitoring, which are present both in the normal mode and in the standby mode, and a control input, to which output voltages are coupled for monitoring, which are only present in the normal mode and a control signal is coupled, by which the power supply unit is switched over between the normal mode and the standby mode, the control signal blocking the switching stage in the standby mode.