Abstract: A control circuit for a single-cell linear oxygen sensor having a first and a second electrical terminals on which a first voltage and respectively a second voltage are present, wherein a cell current between the first and second electrical terminals is indicative of a detected oxygen concentration, and wherein the control circuit generates a biasing voltage between the first and the second electrical terminals with a preset pattern as a function of the cell current. The circuit envisages: a transresistance block, coupled to the second electrical terminal to generate a processed voltage as a function of the cell current and based on the preset pattern; and an adder stage, coupled to the transresistance block and to the second electrical terminal, to perform a sum between the processed voltage and the second voltage, to generate the first voltage for the first electrical terminal of the linear oxygen sensor, so that the biasing voltage has the preset pattern as a function of the cell current.

Abstract: A method performs a diagnosis of a lambda sensor of a “UEGO” type of an exhaust system for an internal-combustion engine. The lambda sensor includes a series of pins. The diagnosis method comprises steps of: heating the lambda sensor to cause the lambda sensor to reach an inner temperature that is higher than about 600° C.; polarizing a first one of the pins by connecting the first pin to a supply voltage through a first limiting resistance; measuring a voltage of all of the pins while the first pin is connected to the supply voltage; and diagnosing a presence of a short circuit to an electrical ground if the voltage of at least one of the pins is lower than a predetermined threshold. A control unit performs the diagnosis.

Abstract: A method performs a diagnosis of a lambda sensor of a “UEGO” type of an exhaust system for an internal-combustion engine. The lambda sensor includes a series of pins. The diagnosis method comprises steps of: heating the lambda sensor to cause the lambda sensor to reach an inner temperature that is higher than about 600° C.; polarizing a first one of the pins by connecting the first pin to a supply voltage through a first limiting resistance; measuring a voltage of all of the pins while the first pin is connected to the supply voltage; and diagnosing a presence of a short circuit to an electrical ground if the voltage of at least one of the pins is lower than a predetermined threshold. A control unit performs the diagnosis.