Low flux and low noise detection circuit

Detection circuit comprising:

• a detector having a stray capacitor, the detector being configured to deliver electric charges according to an observed phenomenon,
• a bias circuit configured to bias the detector during a first period and to leave a first terminal of the detector at a floating potential during a second period,
• a first capacitor having a first terminal connected to the first terminal of the detector to form an integration node with the stray capacitor, the integration node being at a potential target value during the first period and at a changing potential during the second period,
• a transfer circuit configured to transfer electric charges from the stray capacitor to the first capacitor, the transfer circuit being configured to bias a second terminal of the first capacitor so as to shift a potential of the integration node to the potential target value for transferring the electric charges and to disable transfer of the electric charges when the potential of the integration node reaches a predefined value,
• an output terminal delivering a voltage representative of the potential present on the second terminal of the first capacitor.