A low side driver includes a first transistor coupled in series with a second transistor at a low side voltage node for a load. A capacitance is configured to store a voltage and a voltage buffer circuit has an input coupled to receive the voltage stored by the capacitance and an output coupled to drive a control node of the second transistor with the stored voltage. A current source supplies current through a switch to the capacitance and the input of the voltage buffer circuit. The switch is configured to be actuated by an oscillating enable signal so as to cyclically source current from the current source to the capacitance and cause a stepped increase in the stored voltage which is applied by the buffer circuit to the control node of the second transistor.