A DC/DC converter comprising: a plurality of conversion cells (cell1, cell2; 100 ij) connected in parallel and/or in series, each cell comprising at least one switch (T1, T2, T3, T4; T5, T6, T7) and at least one passive power storage element; a diagnosis circuit (BIST) configured to individually test the cells (cell1, cell2; 100 ij) to detect possible defective cells, to deactivate the defective cells, and to store the location of the defective cells; and a general control circuit capable, when cells are deactivated by the diagnosis circuit (BIST), of reconfiguring control sequences applied to the switches (T1, T2, T3, T4; T5, T6, T7) of the cells which are still active, wherein: each cell further comprises an internal control circuit for controlling the at least one switch (T1, T2, T3, T4; T5, T6, T7) of the cell, the internal circuit being adapted to apply to said at least one switch a control sequence that depends on a parameterizing signal (param) provided to the internal control circuit of the cell by the general control circuit of the converter; the general control circuit is configured to define a plurality of elementary groups (GR j) each comprising a plurality of neighboring elementary cells (100 ij), and to apply to the elementary cells of a same group different parameterizing signals (param) so that all the elementary cells in the group cooperate to implement a determined DC/DC conversion function; and the general control circuit is configured, when defective cells are deactivated by the diagnosis circuit (BIST), to reconfigure the parameterizing signals (param) applied to the internal control circuits of the cells (cell1, cell2; 100 ij) which are still active in order to redefine the elementary groups (GR j) of the converter. a plurality of conversion cells (cell1, cell2; 100 ij) connected in parallel and/or in series, each cell comprising at least one switch (T1, T2, T3, T4; T5, T6, T7) and at least one passive power storage element; a diagnosis circuit (BIST) configured to individually test the cells (cell1, cell2; 100 ij) to detect possible defective cells, to deactivate the defective cells, and to store the location of the defective cells; and a general control circuit capable, when cells are deactivated by the diagnosis circuit (BIST), of reconfiguring control sequences applied to the switches (T1, T2, T3, T4; T5, T6, T7) of the cells which are still active, each cell further comprises an internal control circuit for controlling the at least one switch (T1, T2, T3, T4; T5, T6, T7) of the cell, the internal circuit being adapted to apply to said at least one switch a control sequence that depends on a parameterizing signal (param) provided to the internal control circuit of the cell by the general control circuit of the converter; the general control circuit is configured to define a plurality of elementary groups (GR j) each comprising a plurality of neighboring elementary cells (100 ij), and to apply to the elementary cells of a same group different parameterizing signals (param) so that all the elementary cells in the group cooperate to implement a determined DC/DC conversion function; and the general control circuit is configured, when defective cells are deactivated by the diagnosis circuit (BIST), to reconfigure the parameterizing signals (param) applied to the internal control circuits of the cells (cell1, cell2; 100 ij) which are still active in order to redefine the elementary groups (GR j) of the converter.