 ### Several common methods of analysis circuit

- Nov 29, 2016-

Commonly used analytical methods are the following:

1, DC equivalent circuit analysis

In the analysis of the circuit principle, to make clear the circuit in the DC and AC. DC access is defined in the absence of the input signal, the semiconductor transistor, the static bias of the integrated circuit, that is, their static operating point. AC circuit refers to the method of communication signal transmission, the AC signal sequence of events.

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

Analysis of DC equivalent, a method of analysis is to separate the analyzed circuit of DC system in DC equivalent analysis, without considering the processing circuit of input AC signal, only consider the relationship between the static DC power supply DC voltage caused by direct current voltage and between them.

DC equivalent analysis, the first to draw the DC equivalent circuit. The following principles should be followed in the drawing of the DC equivalent circuit: the capacitor is open circuit processing, can ignore the DC resistance of the inductor should be regarded as a short circuit, can not ignore the resistance component of the inductor can be equivalent to the resistance. The voltage of the power supply voltage is taken as the power supply voltage of the equivalent circuit, and the reverse biased state of the semiconductor diode is considered as an open circuit.

2, AC equivalent circuit analysis:

AC equivalent circuit analysis is a method to separate the AC system from the circuit separately.

AC equivalent analysis, first of all, we should draw the AC equivalent circuit diagram. Drawing AC equivalent circuit diagram should follow the following principles: the power is considered as a short circuit, the AC bypass capacitors are all look at the face of the short circuit.

3, time constant analysis method

Time constant analysis method is used to analyze R, L, C and properties of semiconductor diode circuit, the time constant is a reflection of energy storage elements on energy accumulation speed, if different time constants, although the circuit form and the connection is similar, but the circuit function is different. There is a common coupling circuit, differential circuit, integrated circuit, clamp circuit and peak detector circuit etc..

4, frequency characteristic analysis method:

Frequency characteristic analysis method is mainly used to analyze whether the frequency of the circuit itself is compatible with the frequency of the signal processing. Analysis should be a simple calculation of its center frequency, the upper and lower frequencies and frequency band width, etc.. Through the analysis of the circuit properties, such as filtering, notch, resonant frequency selection circuit, etc..