A controller for controlling the switching of a switched mode power supply, SMPS, to regulate an output voltage of the SMPS, the controller comprising: a reference voltage signal generator for generating a variable reference voltage signal (S ref) for regulating the output voltage (V out) of the SMPS, the reference voltage signal generator being configured to ramp the reference voltage signal (S ref); a voltage droop control signal generator for receiving a current indicator signal (S I) that is indicative of an output current (I out) of the SMPS, the voltage droop control signal generator being configured to generate, based on the received current indicator signal (S I), an output voltage droop control signal (S droop) for regulating the output voltage (V out) of the SMPS; and a switching control signal generator for receiving a voltage indicator signal (S Vout) indicative of the output voltage (V out) of the SMPS, the switching control signal generator being configured to generate, based on the voltage indicator signal (S Vout), the reference voltage signal (S ref) and the output voltage droop control signal (S droop), a control signal (S C) for controlling the switching of the SMPS to regulate the output voltage of the SMPS, wherein the voltage droop control signal generator is configured to generate the output voltage droop control signal (S droop) as a first function of the received current indicator signal (S I) when the reference voltage signal generator is ramping the reference voltage signal (S ref), and to generate the output voltage droop control signal (S droop) as a second function of the received current indicator signal (S I) when the reference voltage signal generator has finished ramping the reference voltage signal (S ref), the second function being different from the first function. a reference voltage signal generator for generating a variable reference voltage signal (S ref) for regulating the output voltage (V out) of the SMPS, the reference voltage signal generator being configured to ramp the reference voltage signal (S ref); a voltage droop control signal generator for receiving a current indicator signal (S I) that is indicative of an output current (I out) of the SMPS, the voltage droop control signal generator being configured to generate, based on the received current indicator signal (S I), an output voltage droop control signal (S droop) for regulating the output voltage (V out) of the SMPS; and a switching control signal generator for receiving a voltage indicator signal (S Vout) indicative of the output voltage (V out) of the SMPS, the switching control signal generator being configured to generate, based on the voltage indicator signal (S Vout), the reference voltage signal (S ref) and the output voltage droop control signal (S droop), a control signal (S C) for controlling the switching of the SMPS to regulate the output voltage of the SMPS, wherein the voltage droop control signal generator is configured to generate the output voltage droop control signal (S droop) as a first function of the received current indicator signal (S I) when the reference voltage signal generator is ramping the reference voltage signal (S ref), and to generate the output voltage droop control signal (S droop) as a second function of the received current indicator signal (S I) when the reference voltage signal generator has finished ramping the reference voltage signal (S ref), the second function being different from the first function.