Analyze the circuit method(1)

DC equivalent circuit analysis:

When analyzing the principle of the circuit, it is necessary to find out the DC path and the AC path in the circuit. DC path refers to the static bias of each semiconductor transistor and integrated circuit when there is no input signal.That is, their static operating point. Ac circuit refers to the way of AC signal transmission, that is, the origin of AC signal.

In the actual circuit, AC circuit and DC circuit coexist in the same circuit, they are not simply related to each other, but also different from each other.

The DC equivalent analysis method is a method to analyze the DC system of the analyzed circuit separately. In the DC equivalent analysis, the processing function of the circuit to the input AC signal is completely ignored. Only the static DC current, voltage caused directly by the DC voltage of the power supply and their relationship is considered.

In DC equivalent analysis, the DC equivalent circuit diagram should be fired first. The following principles should be followed when drawing the DC equivalent circuit diagram: All capacitors are treated by open circuit, inductors that can ignore DC resistance should be regarded as a short circuit, inductors that cannot ignore resistance components can be equivalent to resistors. The decoupling voltage is considered as the supply voltage of the equivalent circuit, and the reverse bias semiconductor diode is regarded as an open circuit.