Polarity sensing circuit

摘要

A dc input circuit receives a dc input voltage. At least four rectification elements are coupled to each other in a diode bridge configuration, where an input of the diode bridge configuration is coupled to the dc input circuit to receive the dc input voltage. At least one of the rectification elements includes a transistor. A decision circuit indicates, as a function of one of collector current and emitter current of the transistor, that the received dc input voltage has normal or reversed polarity. Other embodiments are also described and claimed.

主权项

1. A polarity sensing circuit comprising:
a dc input circuit to receive a dc input voltage; at least four rectification elements coupled to each other in a diode bridge configuration whose input is coupled to the dc input circuit to receive the dc input voltage, wherein at least one of the rectification elements comprises a transistor with a control electrode in a current path of the diode bridge configuration that conducts a current from the input of the diode bridge configuration through the transistor to an output of the diode bridge configuration; and a decision circuit coupled to the transistor, the decision circuit to indicate, as function of the current conducted by the transistor, that the received dc input voltage has normal or reversed polarity.