Gas sensor control device

A gas sensor control device for controlling a gas sensor, said gas sensor comprising a gas sensor element including a cell comprising a solid electrolyte and a pair of electrodes disposed on the solid electrolyte for detecting concentration of a specific gas component, said gas sensor control device comprising:

• a circuit board electrically connectable to the gas sensor via an electrical conductor;
• a voltage control unit mounted on the circuit board and configured to control a voltage developed across the pair of electrodes of the cell to a constant voltage;
• a temperature detecting unit mounted on the circuit board and configured to detect a temperature of the circuit board;
• and
• a voltage correcting unit mounted on the circuit board and configured to apply a correction voltage to the voltage control unit compensating for a temperature-dependent variation in the level of the constant voltage based on the temperature detected by the temperature detecting unit,
• wherein the gas sensor element comprises a plurality of the cells including a first cell and a second cell,
• wherein said gas sensor further comprises a plurality of the voltage control units comprising a first voltage control unit and a second voltage control unit connected to the first cell and the second cell, respectively, the first voltage control unit and the second voltage control unit configured to maintain the voltage developed across the pair of electrodes of the first cell and developed across the second cell to first and second constant voltages, respectively, and
• wherein the voltage correcting unit is configured to apply the correction voltage to only one of the first voltage control unit and the second voltage control unit based on the temperature detected by the temperature detecting unit, the correction voltage compensating a temperature-dependent variation in a voltage difference between the voltage developed across the pair of electrodes of the first cell and the voltage developed across the pair of electrodes of the second cell, and
• an inter-terminal voltage difference is maintained constant regardless of a temperature variation of the circuit board.