In the electronic circuit, the decoupling capacitor and the bypass capacitor plays the role of anti-interference, capacitance in different positions has different names. For the same circuit, bypass (bypass) capacitor is the input signal in the high-frequency noise as the filter object, removing the high-frequency clutter carried by the previous level filter, and decoupling (decoupling) capacitance, also known as decoupling Capacitance taking the interference of the output signal as a filter object.

We can often see, the decoupling capacitor is connected between the power and ground and has three aspects: First, as the  storage capacitor of integrated circuit; Second, filter out the device to produce high-frequency noise, cut off  the channel its through the power supply circuit; third, prevent the power from carrying the noise to disturb the circuit.