An electronic circuit for radiation detector comprising: • a radiation-sensitive element, • an injection circuit, suitable for injecting a charge at a terminal of the sensitive element, the injection circuit extending between at least one input terminal and one output terminal, the output terminal being suitable for being connected to said sensitive element, the injection circuit having an output potential and being suitable for producing a charge under the effect of a trigger pulse, • a comparator having a switchover potential (V comp_bascul) with a first input receiving a threshold potential and a second input suitable for being connected to an integration node that can store electrical charges generated by the sensitive element on reception of the radiation, the charges bringing about a variation of a potential at the integration node, the injection circuit being suitable for injecting charges at the integration node on each switchover of the comparator, until the potential at the integration node reaches or exceeds an equilibrium potential (V equ), • the injection circuit is suitable for injecting a first charge (Q1, Qtot 1) when an input terminal is connected to a first input potential (V_inj_1, Phi_inj_1, Vg1, Vg2) and a second charge (Q2, Qtot 2) when an input terminal is connected to a second input potential (V_inj_2, Phi_inj_2, Vg1, Vg2), characterized in that: • the electronic circuit for radiation detector comprises a means for storing a difference between an equilibrium potential and the switchover potential (V_comp_bascul) which corresponds to the switchover potential of the comparator, the equilibrium potential corresponding to an input potential (V_inj_1) of the injection circuit after one or more injections of the first charge, the storage means being connected to an input of the comparator and the output terminal of the injection circuit, the input of the comparator being able to be connected to an output of the comparator, so that during an injection of a first load, said input of the comparator is connected to the output of the comparator; • in that the storage means comprises a third switch (I_3) connected between the second input of the comparator and the output of the comparator; • and in that the injection circuit is suitable for injecting a second charge (Q2, Qtot 2) dependent on the second input potential (V_inj_2, Phi_inj_2, Vg1, Vg2) and on said equilibrium potential (V equ) corresponding to the first entry potential. • a radiation-sensitive element, • an injection circuit, suitable for injecting a charge at a terminal of the sensitive element, the injection circuit extending between at least one input terminal and one output terminal, the output terminal being suitable for being connected to said sensitive element, the injection circuit having an output potential and being suitable for producing a charge under the effect of a trigger pulse, • a comparator having a switchover potential (V comp_bascul) with a first input receiving a threshold potential and a second input suitable for being connected to an integration node that can store electrical charges generated by the sensitive element on reception of the radiation, the charges bringing about a variation of a potential at the integration node, the injection circuit being suitable for injecting charges at the integration node on each switchover of the comparator, until the potential at the integration node reaches or exceeds an equilibrium potential (V equ), • the injection circuit is suitable for injecting a first charge (Q1, Qtot 1) when an input terminal is connected to a first input potential (V_inj_1, Phi_inj_1, Vg1, Vg2) and a second charge (Q2, Qtot 2) when an input terminal is connected to a second input potential (V_inj_2, Phi_inj_2, Vg1, Vg2), • the electronic circuit for radiation detector comprises a means for storing a difference between an equilibrium potential and the switchover potential (V_comp_bascul) which corresponds to the switchover potential of the comparator, the equilibrium potential corresponding to an input potential (V_inj_1) of the injection circuit after one or more injections of the first charge, the storage means being connected to an input of the comparator and the output terminal of the injection circuit, the input of the comparator being able to be connected to an output of the comparator, so that during an injection of a first load, said input of the comparator is connected to the output of the comparator; • in that the storage means comprises a third switch (I_3) connected between the second input of the comparator and the output of the comparator; • and in that the injection circuit is suitable for injecting a second charge (Q2, Qtot 2) dependent on the second input potential (V_inj_2, Phi_inj_2, Vg1, Vg2) and on said equilibrium potential (V equ) corresponding to the first entry potential.