| 摘要 |
The invention relates to a circuit arrangement which is used for stepping up an electrical voltage which exists between a first conductor (1) and a second conductor (2) in a motor vehicle. In this case, an inductive store (5) having a downstream-connected blocking diode (6) is inserted into the first conductor (1). In addition, the line section which exists between the inductive store (5) and the blocking diode (6) is the point of origin for a connection which leads via the emitter-collector junction of a switching transistor (7) to the second conductor (2). Furthermore, the conductor section after the blocking diode (6) is the point of origin for a connection which leads via a capacitive store (8) to the second conductor (2). Finally, a comparator (9) is provided which is used for comparing the stepped-up voltage with a voltage setting and for securing the switching transistor against switching on. According to the invention, an auxiliary winding (10) is inductively coupled to the inductive store (5), with the aid of which auxiliary winding (10) the switching transistor (7) is continuously switched on and off when a voltage which is to be stepped up is present upstream of the inductive store (5) and the switching transistor (7) is not secured against switching on. In this way, a circuit arrangement is obtained which is of simple construction and is reliable in operation. <IMAGE>
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