Image sensing microelectronic device comprising: at least one detector formed of at least one photodetector element, at least one integration capacitor associated with the photodetector and capable of delivering at least one analog signal (Vint) able to vary at least in relation to quantities of photons received by the photodetector, a counter and asynchronous analog/digital conversion means comprising: - a comparator able to receive an analog signal (Vint) from said integration capacitor and to deliver a two-statess output signal (Scomp) which, in relation to the analog signal (Vint), is able to be in a first state called "stable state" or in a second state, - charge injector means able to modify the analog signal (Vint) by injecting at least a quantity of charges (Qo) into said capacitor, - asynchronous command means commanding the charge injector means, able to receive the two-states signal (Scomp) and configured for commanding the injector means, the device being characterized in that command means comprise: • means (171, 178, 181, 184) to identify at least a state change of the signal (Scomp) output by the comparator, from the first state to the second state, the state change allowing to generate a command edge, • means (171, 178, 181, 184, 185) to trigger automatically and asynchronously, consecutively of an identification of a state change by said means to identify a change of the state, several consecutive charge injections Q 0 by the injector means, injections being triggered by said command edge and executed as long as the output signal (Scomp) leaving the comparator is held in the second state, analog/digital converting means able to deliver a digital signal to said counter configured to count a number of injections performed by said charge injector means during a given period from a control signal of the charge injector means, this count being intended to give a numerical value of charges from the photodetector. - a comparator able to receive an analog signal (Vint) from said integration capacitor and to deliver a two-statess output signal (Scomp) which, in relation to the analog signal (Vint), is able to be in a first state called "stable state" or in a second state, - charge injector means able to modify the analog signal (Vint) by injecting at least a quantity of charges (Qo) into said capacitor, - asynchronous command means commanding the charge injector means, able to receive the two-states signal (Scomp) and configured for commanding the injector means, the device being characterized in that command means comprise: • means (171, 178, 181, 184) to identify at least a state change of the signal (Scomp) output by the comparator, from the first state to the second state, the state change allowing to generate a command edge, • means (171, 178, 181, 184, 185) to trigger automatically and asynchronously, consecutively of an identification of a state change by said means to identify a change of the state, several consecutive charge injections Q 0 by the injector means, injections being triggered by said command edge and executed as long as the output signal (Scomp) leaving the comparator is held in the second state, • means (171, 178, 181, 184) to identify at least a state change of the signal (Scomp) output by the comparator, from the first state to the second state, the state change allowing to generate a command edge, • means (171, 178, 181, 184, 185) to trigger automatically and asynchronously, consecutively of an identification of a state change by said means to identify a change of the state, several consecutive charge injections Q 0 by the injector means, injections being triggered by said command edge and executed as long as the output signal (Scomp) leaving the comparator is held in the second state,