Current-measurement device

A device for measuring current by means of integration, said device comprising:

• a first operational amplifier comprising a first inverting input, with the current to be measured being applied on said first inverting input;
• an integration capacitor arranged between the first inverting input of the first operational amplifier and an output of said first operational amplifier;
• an active current source connected to the first inverting input of the first operational amplifier, with the current source being configured to:
• in a first measurement state of the device, compensate for leakage current of the device;
• in a second reset state of the device, triggered by a charge value of the integration capacitor substantially equal to a maximum value QMax that it can have, generate a current which is adapted to return said charge to its initial value Q0;
• a control system configured to:
• memorise a Q0 initial charge state of the integration capacitor, corresponding to a voltage Vco at the output of the first operational amplifier;
• place the device in the measurement state and keep it there until the charge of the integration capacitor substantially reaches QMax, corresponding to a voltage VCMax at the output of the first operational amplifier;
• when the charge of the integration capacitor substantially reaches QMax, corresponding to a voltage VCMax at the output of the first operational amplifier, place the device in the reset state until the charge of the integration capacitor substantially reaches Q0.