Inverter circuits have bridge branches which, for. B. consist of two series-connected transistors (T1, T2), each with a free-wheeling diode (D1, D 2). A critical operating state occurs when the freewheeling current is commutated by one diode (D1, D2) by switching on the other transistor (T2; T1). The reverse current through this diode can take on such high values when this transistor is switched on quickly that the "dynamic" blocking capability of the diode is exceeded and the diode is destroyed. The load current and the control current of the transistor are therefore fed back so that the transistor switches on more slowly and temporarily takes over part of the voltage otherwise present at the diode.
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