Nearly every electronic circuit today needs several different supply voltages. A suitable power-management architecture must be designed for the different required voltage rails. Typically, multiple voltage converters working according to the switching regulator principle are used. In this design approach, each of these switching regulators needs an inductor.
For an end-product, it’s often important to use as little PCB space as possible and that the associated costs be as low as possible. A popular way to accomplish those goals is by taking the integration route. Integrating the circuit into the silicon works well for switching regulators and linear regulators at low power.