| CPC H03K 17/18 (2013.01) [H02M 1/32 (2013.01); H03K 2017/307 (2013.01)] | 17 Claims |

|
1. A method for checking at least one field effect transistor connected as an active diode, downstream of an output of a power supply unit within a power supply device, comprising the steps of:
(a) generating a blocking state of the at least one field effect transistor;
(b) detecting a first value of a voltage drop across a switching path of the at least one field effect transistor at a first set voltage of the power supply unit;
(c) setting a second voltage of the power supply unit;
(d) detecting a second value of the voltage drop across the switching path of the at least one field effect transistor at the second set voltage of the power supply unit; and
(e) detecting and signaling a defect of the at least one field effect transistor if the first value of the voltage drop and the second value of the voltage drop are both smaller in magnitude than a predetermined first positive threshold value, or if the first value of the voltage drop and/or the second value of the voltage drop are larger than a predetermined second positive threshold value, wherein the second threshold value is larger than the first threshold value.
|