A device and a method for biasing a transistor connected to a voltage converter, the method includes: (i) providing at least one bias voltage to at least one well of at least one transistor of a test circuitry; (ii) measuring at least one parameter of a test circuitry representative of at least one characteristic of the transistor and of at least one characteristic of the voltage converter; (iii) altering at least one bias voltage and repeating the stages of providing and measuring until a predefined control criteria is fulfilled; and (iv) providing a voltage bias to a well of the transistor in response to the measurements. The device includes: (i) at least one transistor; (ii) at least one voltage converter, connected to the at least one well of at least one transistor, for providing at least one bias voltage; (iii) a test circuitry, connected to the at least one voltage converter, adapted to: (a) measure at least one parameter of the test circuitry representative of at least one characteristic of the transistor and of at least one characteristic of the voltage converter; (b) alter at least one bias voltage provided to the test circuitry and measure at least one parameter, until a control criterion is fulfilled; and (c) determine, in response to the at least one measured parameter, at least bias voltage to be provided to at least one well of the at least one transistor.