How to analyze DC circuit and AC circuit in PCB circuit board design?

DC equivalent circuit analysis method: The DC equivalent analysis method is a method for separately analyzing the DC system of the circuit being analyzed. When performing the DC equivalent analysis, the circuit's processing function of the input AC signal is not considered at all. Only the static DC current and voltage directly caused by the DC voltage of the power supply and their mutual relationship are considered. In the DC equivalent analysis, the DC equivalent circuit diagram should be drawn first. When drawing a DC equivalent circuit diagram, the following principles should be followed: all capacitors are treated as open circuits, and inductors that can ignore DC resistance should be regarded as short circuits, and inductors that cannot ignore resistance components can be equivalent to resistance. The voltage after decoupling is taken as the supply voltage of the equivalent circuit; the semiconductor diode in the reverse bias state is regarded as an open circuit.


The AC system in a circuit is separated from the circuit and is a method for separate analysis. When analyzing the AC equivalent, you should first draw the AC equivalent circuit diagram. Drawing the AC equivalent circuit diagram should follow the following principles: treat the power supply as a short circuit, treat the AC bypass capacitor as a short circuit, and see the DC blocking coupler as a short circuit.


In summary, when analyzing the circuit principle of the CAM OEM Yoko board, it is necessary to clarify the DC path and AC path in the circuit. The 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 transmission path of AC signals, that is, the ins and outs of AC signals. In the actual circuit, the AC circuit and the DC circuit coexist in the same circuit, and they are both related to each other and different from each other.