A system or module has a 3-or-more layer current-controlled switching device, such as a bipolar power transistor, for driving a load and a base driver circuit coupled to drive it. The driver has a buck-converter configuration for efficiently driving the switching device. In an embodiment, the driver has an inductor, the inductor having a first terminal coupled to a base of the bipolar junction transistor, a high-side switching device coupled to drive a second terminal of the inductor; and a rectification device coupled to the second terminal of the inductor. The driver also has a control circuit for providing a sequence of pulses through the high-side switching device when a control signal indicates the bipolar junction transistor is to be turned on.