Electrical circuit, particularly an electronic power circuit for motor vehicle injection systems, with a function for the detection and diagnosis of faults, and the related method

An electrical circuit including at least one stage with an output terminal for supplying a respective load,

• the circuit admitting of a plurality of faulty conditions as well as a normal operating condition, said circuit comprising:
• means for generating at least one first signal indicating that the circuit is in one of the plurality of faulty conditions;
• means for generating at least one second signal which assumes different values in accordance with the plurality of faulty conditions, respectively, so as to identify which one of the plurality of faulty conditions is present in the circuit;
• first sensor means for sensing a voltage applied to the load by the output terminal;
• second sensor means for sensing a current applied to the load by the output terminal;
• first comparator means, connected to the first sensor means and defining a range of permitted values for a voltage applied to the load during the normal operating condition of the circuit, the first comparator means operable for generating a first logic signal which assumes a first value or a second value in accordance with whether the voltage applied to the load is inside or outside the range of permitted values, respectively;
• second comparator means, connected to the second sensor means and defining a range of permitted values for a current applied to the load during the normal operation condition of the circuit, the second comparator means being operable for generating a second logic signal which assumes a first value or a second value in accordance with whether the current applied to the load is inside or outside the range of permitted current values, respectively;
• and
• logic processor means, connected to receive the first logic signal and the second logic signal, said logic processor means being operable for generating the at least one second signal with different values in accordance with a distribution of values assumed by the first and second logic signals.