The invention relates to a switched mode power supply with current mode control, in which an inductive element (7) is connected to a power source (5) by means of a controllable switch (9). During closure of the switch (9) the increasing current through the inductive element (7) is sensed by a current sensor (17) and compared with a reference signal (18). When the signal from the current sensor is equal to the reference signal, the switch (9) is opened. Due to circuitry delays the off-switching of the switch (9) occurs at a higher current level than sensed by the current sensor (17). To compensate for this effect the switched mode power supply has means (16, 19, 15) for generating a compensation signal (Ic*R15) proportional to the gradient (di/dt) of the current i through the inductive element (7). The circuitry delay can be compensated for by a suitable choice of values of components (15, 19, 16).