Views:0 Author:Site Editor Publish Time: 2019-05-22 Origin:Site
Capacitors should know that there is such a thing, because there is a capacitor in every household's electrical appliances. Although there are many people using metal film capacitors, there is very little understanding of the role of metal film capacitors, so today Xiaobian Let's talk about the role of metal film capacitors.
1. DC blocking. This not only makes the role of the metal film capacitor, but also the basic function of all capacitors, which is to prevent the passage of DC and let the AC pass.
2. Coupling. The coupling of the metal film capacitor acts as a connection between the two circuits, allowing the AC signal to pass through and be transmitted to the lower stage circuit. Coupling is used as a component in the circuit to pass the previous signal to the back and to isolate the previous influence on the subsequent stage, which makes the debugging of the circuit simpler and the performance more stable.
3. Filtering. The filtering function of the capacitor is very important in the circuit. The capacitance behind the CPU is basically this function. When the capacitor uses the filtering function, the larger the frequency f, the smaller the impedance Z of the capacitor. When the frequency is low, the capacitance C is relatively large due to the impedance Z, and the useful signal can pass smoothly. When the high frequency is used, the capacitance C is small due to the impedance Z, which is equivalent to short-circuiting the high-frequency noise to the GND.
4. Bypass: The capacitor used in the bypass circuit is called bypass capacitor. If the signal in a certain frequency band needs to be removed from the signal, the bypass capacitor circuit can be used. According to the frequency of the removed signal, there is full frequency. Domain bypass capacitor circuit and high frequency bypass capacitor circuit.
5. Temperature compensation. The temperature compensation function of the capacitor is mainly for the influence of the insufficient adaptability of other components to the temperature, thereby compensating by the capacitor to improve the stability of the circuit.
6. High-frequency vibration reduction: The capacitor used in the high-frequency vibration-absorbing circuit is called the high-frequency vibration-absorbing capacitor. In the audio negative feedback amplifier, in order to eliminate the high-frequency self-excitation that may occur, this capacitor circuit is used. Eliminate the high frequency howling that the amplifier may appear.
7, neutralization. The capacitor used in the neutralization circuit is called a neutralization capacitor. In radio high frequency and intermediate frequency amplifiers, TV high frequency amplifiers, this neutralization capacitor circuit is used to eliminate self-excitation.
8, timing. The capacitor used in the timing circuit is called a timing capacitor. A timing capacitor circuit is used in a circuit that requires time control by capacitor charging and discharging, and the capacitor controls the magnitude of the time constant.
The main function of the metal film capacitor is the above. If you have technical questions, please contact us, we will try our best to solve it for you.