Driver circuits (1) for driving load circuits (2, 3) receive source signals from sources and provide feeding signals to the load circuits (2,3) and charging signals to capacitor circuits (21). These capacitor circuits (21) provide supporting signals to the load circuits (2, 3) in addition to the feeding signals. By providing the driver circuits (1) with control circuits (22) for controlling the supporting signals, the capacitor circuits (21) can become less bulky/costly and/or will limit the lifetime of the driver circuits (1) to a smaller extent. Further, these driver circuits (1) may get improved efficiencies. Said controlling may comprise controlling moments in time at which the supporting signals are offered to the load circuits (2, 3) or not, and/or may comprise controlling sizes of the supporting signals, and/or may be done in response to detection results from detectors (23) for detecting parameters of one or more signals. Said controlling may comprise switching via switches (24).