Apparatus and method for recognizing an error in a power bridge circuit

摘要

An apparatus and a method for recognizing an error in a power bridge circuit containing a load, a high-side branch and a low-side branch. Accordingly, a first switched current source is connected to the load and to a diagnosis connection for a high-potential of a diagnosis voltage, a second switched current source is connected to the load and to a diagnosis connection for a low-potential of the diagnosis voltage, and a control device for controlling the first switched current source and the second switched current source. The control device switches on one of the switched current sources when the high-side power switch and the low-side power switch are open, while the other switched current source is switched off. A testing device tests a voltage at the load when one of the switched current sources is switched on and the other of the switched current sources is switched off.

主权项

1. An apparatus for recognizing an error in a power bridge circuit having a load with a high-side connection and a low-side connection, a high-side branch having a high-side power switch connected between the high-side connection of the load and a supply connection for a high-potential of a supply voltage, and a low-side branch having a low-side power switch connected between the low-side connection of the load and a supply connection for a low-potential of the supply voltage, the apparatus comprising:
a first switched current source connected to the load and having a diagnosis connection for a high-potential of a diagnosis voltage; a second switched current source connected to the high-side connection of the load and having a diagnosis connection for a low-potential of the diagnosis voltage; a control device for controlling said first switched current source and said second switched current source, said control device configured such that when the high-side power switch is open and the low-side power switch is open, said control device switches on one of said first and second switched current sources, while the other of said first and second switched current sources is switched off, and then said control device switches off one of said first and second switched current sources and switches on the other of said first and second switched current sources; a third switched current source connected to the low-side connection of the load and to said diagnosis connection for the high-potential of the diagnosis voltage, said control device connected to said third switched current source to control said third switched current source; and a testing device for testing a voltage at the load when one of said first and second switched current sources is switched on and the other of said first and second switched current sources is switched off, and when said one of said first and second switched current sources is switched off and said other of said first and second switched current sources is switched on; said testing device connected to the low-side connection of the load, and the voltage at the load to be tested by said testing device being a low-side voltage occurring at the low-side connection of the load.