A switched current control module comprising: a hysteretic control component arranged to receive a high threshold value signal, a low threshold value signal and an indication of a current flow through a load, and to output a switched current control signal based on a comparison of the current flow indication to the high and low threshold value signals (212, 214); a threshold generator component arranged to generate the high and low threshold value signals (212, 214) based on a base threshold value signal and a hysteretic excursion value signal; a base threshold value generator component arranged to receive the current flow indication and a setpoint value, and to generate the base threshold value signal based on the received current flow indication and setpoint value; and a hysteretic excursion value generator component arranged to receive an indication of a switching frequency of the switched current control signal output by the hysteretic control component, and to generate the hysteretic excursion value signal based on the indicated switching frequency of the switched current control signal; characterized in that the base threshold value generator component is arranged to determine an average current error value for the current flow through the load based on the received indication of current flow through the load and setpoint value, and to generate the base threshold value signal proportional to the determined average current error value; and the hysteretic excursion value generator component is arranged to derive a switching frequency value inversely proportional to the indicated switching frequency of the switched current control signal and to subtract the switching frequency value from a reference value to generate the hysteretic excursion value signal. a hysteretic control component arranged to receive a high threshold value signal, a low threshold value signal and an indication of a current flow through a load, and to output a switched current control signal based on a comparison of the current flow indication to the high and low threshold value signals (212, 214); a threshold generator component arranged to generate the high and low threshold value signals (212, 214) based on a base threshold value signal and a hysteretic excursion value signal; a base threshold value generator component arranged to receive the current flow indication and a setpoint value, and to generate the base threshold value signal based on the received current flow indication and setpoint value; and a hysteretic excursion value generator component arranged to receive an indication of a switching frequency of the switched current control signal output by the hysteretic control component, and to generate the hysteretic excursion value signal based on the indicated switching frequency of the switched current control signal; characterized in that the base threshold value generator component is arranged to determine an average current error value for the current flow through the load based on the received indication of current flow through the load and setpoint value, and to generate the base threshold value signal proportional to the determined average current error value; and the hysteretic excursion value generator component is arranged to derive a switching frequency value inversely proportional to the indicated switching frequency of the switched current control signal and to subtract the switching frequency value from a reference value to generate the hysteretic excursion value signal.