This is the technical term for
integration of
logic and
power microelectronics. Think of a
control of the electric windows in your car. You need some logic stuff (to connect to the internal data bus, to receive signals from the
sensors that tell if the
window is already closed or blocked by, say, the neck of your
daughter). To drive the
motor, you need power stuff, electronics that works at a higher
voltage and/or electrical power. Before you had one
logic chip and one power
chip, now you use just one.
Cheaper.
Smaller.
From the semiconductor perspective, this is done by taking your favourite CMOS-process (logic stuff) and adding diffusions to handle higher voltages. These are usually lower doped and go deeper under the surface.