In radio communications, broadcast television, and auto […]
In radio communications, broadcast television, and automatic control, it is used as a component of voltage amplification, power output and other circuits. The audio transformer has a uniform frequency response in the working frequency band, and its core is made of high-permeability materials. The primary and secondary windings are tightly coupled, so that almost all the magnetic flux passing through the primary winding is linked with the secondary winding, and the coupling coefficient is close to 1.
The lowest frequency of the passband is determined by the inductance of the original winding, and the highest frequency is determined by the leakage inductance of the transformer. To ensure that the transformer has enough pass band, the original winding inductance should be large, and the leakage inductance should be small. The hysteresis loss of the iron core and the saturation of the magnetic circuit will cause signal distortion.
Properly configure the load and increase the load current to reduce the effect of hysteresis loss; increase the core section and leave an air gap to prevent the magnetic circuit from being saturated, which can reduce signal distortion.
Audio transformers can be divided into three categories according to their position in the electronic circuit.
1. Connected between the output circuit and the load is called the output transformer;
2. The one connected between the signal source and the input of the amplifier is called the input transformer;
3. Connected between the output circuit of the upper stage and the input circuit of the next stage is called an interstage transformer.
Attention should be paid to the matching of the front and rear impedances to avoid signal distortion due to reflections. In order to make the load obtain the maximum power, the load impedance should be consistent with the impedance required by the power amplifier stage after the transformation through the impedance of the output transformer, and it should not be too large or too small. After the audio signal is amplified by the audio transformer, although the voltage can be increased, the power is reduced due to the loss of the transformer. In this way, it cannot drive a larger load. Therefore, audio transformers cannot replace electronic audio signal amplifiers.
Zhejiang Dechuang Transformer Manufacturing Co., Ltd.
