# What is the basic amplifier circuit of the car module?

Last Update Time: 2019-08-07 10:53:38

The concept of zooming is no stranger to you. The microscope amplifies the cells. The principle of leverage gives me a fulcrum. I can lift the whole earth. The energy of the transformer voltage is converted to low voltage and high voltage. These are all aspects of amplification. They have two characteristics. One is to scale the object proportionally, and the other is to follow the law of conservation of energy after amplification. A circuit capable of amplifying a weak signal is called an amplifying circuit or an amplifier. For example, the key component in a hearing aid is an amplifier.

The amplifier has an AC amplifier and a DC amplifier. The AC amplifier can be divided into low frequency, medium source and high frequency according to frequency; the output signal strength is divided into voltage amplification and power amplification. There are also amplifiers that use integrated op amps and special transistors as devices. It is the most complex and variable circuit in electronic circuits. But beginners often encounter only a few typical analog circuits.

Today, I will briefly talk about the amplifying circuit in electricity. The amplification of the sound in our common car, that is, the amplification of the speaker, illustrates the concept of amplification in automotive electronics.

When reading the magnifying circuit diagram, it is also carried out according to the principles and steps of “gradual decomposition, seizing key, careful analysis, and comprehensive integration”. First, the entire amplifying circuit is separated step by step according to the input and output, and then the key is grasped step by step to analyze and clear the principle. Amplifying circuit has its own characteristics: First, there are two working states, static and dynamic, so sometimes it is necessary to draw its DC path and AC path to analyze; Second, the circuit often adds negative feedback.  In this level, sometimes it is feedback from the latter level to the predecessor level, so it is necessary to be able to “see ahead” when analyzing this level. After the principle of each level is solved, the entire circuit can be connected for comprehensive synthesis.

As can be seen from the above figure, There is a power supply in the amplifying circuit, which has a common grounding. When the speaker speaks, a weak electrical signal is generated through the microphone. After the electrical signal is processed by the amplifying circuit, it is converted into a sufficiently powerful electrical signal to drive the speaker to vibrate. It amplifies the sound and also converts the original weak electrical signal (power) into a powerful output power. This leads to two points:

1, the essence of the amplifier circuit is energy amplification, that is, power amplification, it can be said that the speaker in the above picture will always get more energy than the input signal, sometimes the voltage is increased, sometimes the current is increased.

2, the object of magnification is the amount of change.

The primary factor of amplification is no distortion, which is what we need. The most important components of the amplifier circuit are transistors and FETs. Only when they work in the specification area can the input and output be linearly related. Any waveform can be superimposed by harmonics, so the test signal of the amplifying circuit is a sine wave. The main performance indicators of the amplifying circuit will be supplemented by the part of the amplifying circuit.

If you want to know more, our website has product specifications for the amplifier, you can go to ALLICDATA ELECTRONICS LIMITED to get more information