The invention provides a current modulating circuit, for example for use in a driving circuit for driving a lighting load such as an LED arrangement. A current modulating element is provided in series with the lighting load, and modulates the current based on a data input signal. A feedback system controls the current modulating element, and it has a first feedback control path which uses a voltage across the current modulating element, and a second feedback control path which uses the data input signal. The voltage feedback is used to maintain the overall current equal to the current output from a driver. The difference in current is taken up by a capacitor at the output of the driver.