As long as the capacitor C is large enough, with only a small voltage change, the capacitor can provide a large enough current to meet the load transient current requirements. This ensures that the variation of the load chip voltage is within the allowable range. Here, it is equivalent to that the capacitor stores a part of the electric energy in advance and releases it when the load needs it, that is, the capacitor is an energy storage element. The existence of the energy storage capacitor can quickly replenish the consumption of the load, thus ensuring that the voltage across the load does not change too much. At this time, the capacitor plays the role of a local power supply.