A circuit comprising: a photodiode configured to absorb photons and to generate photo-carriers from the absorbed photons; a first MOSFET transistor comprising: a first channel terminal coupled to a first terminal of the photodiode and configured to collect a portion of the photo-carriers generated by the photodiode; a second channel terminal; and a gate terminal coupled to a first control voltage source; a first readout circuit configured to output a first readout voltage, the first readout circuit comprising: a first capacitor configured to integrate the photo-carriers generated by the photodiode; and a first reset MOSFET transistor configured to charge the first capacitor to a first voltage; a second readout circuit configured to output a second readout voltage, the second readout circuit comprising: a second capacitor configured to integrate the photo-carriers generated by the photodiode; and a second reset MOSFET transistor configured to charge the second capacitor to a second voltage; and a current-steering circuit configured to steer the photo-carriers generated by the photodiode to one or both of the first readout circuit and the second readout circuit, the current-steering circuit comprising: a first current-steering MOSFET transistor comprising a second gate terminal coupled to a second control voltage source, a third channel terminal coupled to the second channel terminal, and a fourth channel terminal coupled to the first readout circuit; and characterised by a second current-steering MOSFET transistor comprising a third gate terminal coupled to a third control voltage source, a fifth channel terminal coupled to the second channel terminal, and a sixth channel terminal coupled to the second readout circuit, wherein, during operation of the circuit, the first control voltage source generates a first control voltage configured to create a first voltage difference between the first voltage and a third voltage of the first terminal of the photodiode, and to create a second voltage difference between the second voltage and the third voltage of the first terminal of the photodiode. a photodiode configured to absorb photons and to generate photo-carriers from the absorbed photons; a first MOSFET transistor comprising: a first channel terminal coupled to a first terminal of the photodiode and configured to collect a portion of the photo-carriers generated by the photodiode; a second channel terminal; and a gate terminal coupled to a first control voltage source; a first channel terminal coupled to a first terminal of the photodiode and configured to collect a portion of the photo-carriers generated by the photodiode; a second channel terminal; and a gate terminal coupled to a first control voltage source; a first readout circuit configured to output a first readout voltage, the first readout circuit comprising: a first capacitor configured to integrate the photo-carriers generated by the photodiode; and a first reset MOSFET transistor configured to charge the first capacitor to a first voltage; a first capacitor configured to integrate the photo-carriers generated by the photodiode; and a first reset MOSFET transistor configured to charge the first capacitor to a first voltage; a second readout circuit configured to output a second readout voltage, the second readout circuit comprising: a second capacitor configured to integrate the photo-carriers generated by the photodiode; and a second reset MOSFET transistor configured to charge the second capacitor to a second voltage; and a second capacitor configured to integrate the photo-carriers generated by the photodiode; and a second reset MOSFET transistor configured to charge the second capacitor to a second voltage; and a current-steering circuit configured to steer the photo-carriers generated by the photodiode to one or both of the first readout circuit and the second readout circuit, the current-steering circuit comprising: a first current-steering MOSFET transistor comprising a second gate terminal coupled to a second control voltage source, a third channel terminal coupled to the second channel terminal, and a fourth channel terminal coupled to the first readout circuit; and characterised by a second current-steering MOSFET transistor comprising a third gate terminal coupled to a third control voltage source, a fifth channel terminal coupled to the second channel terminal, and a sixth channel terminal coupled to the second readout circuit, a first current-steering MOSFET transistor comprising a second gate terminal coupled to a second control voltage source, a third channel terminal coupled to the second channel terminal, and a fourth channel terminal coupled to the first readout circuit; and characterised by a second current-steering MOSFET transistor comprising a third gate terminal coupled to a third control voltage source, a fifth channel terminal coupled to the second channel terminal, and a sixth channel terminal coupled to the second readout circuit, wherein, during operation of the circuit, the first control voltage source generates a first control voltage configured to create a first voltage difference between the first voltage and a third voltage of the first terminal of the photodiode, and to create a second voltage difference between the second voltage and the third voltage of the first terminal of the photodiode.