脈寬調制和DC - DC轉換(PWM & DC-DC Converter)培圳資料:What Is a Switching Regulator?

A switching regulator is a circuit that uses an inductor, a transformer, or a capacitor as an energy-storage element to transfer energy from input to output in discrete packets. Feedback circuitry regulates the energy transfer to maintain a constant voltage within the load limits of the circuit.

The basic circuit can be configured to step up (boost), step down (buck), or invert output voltage with respect to input voltage.

Why Use a Switching Regulator?

For battery management, the only other choice is a linear regulator. Linear regulators only step down, and efficiency is equivalent to the output voltage divided by the input voltage. On the other hand, switching regulators operate by passing energy in discrete packets over a low-resistance switch, so they can step up, step down, and invert. In addition, they offer higher efficiency than linear regulators.
Using a transformer as the energy-storage element also allows the output voltage to be electrically isolated from the input voltage.

The one disadvantage of the switching regulator is noise. Any time you move charge in discrete packets, you create noise or ripple. But the noise can often be minimized using specific control techniques and through careful component selection.