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Nicaragua the switching frequency of the AC-DC switching power supply module?(4)

2022-09-22

When testing electronic and electrical equipment, the electronic and electrical equipment shall be tested for conducted interference voltage emission at its Marine boost power supply terminal. Although the test frequency bands of different standards are different, the test frequency bands of most products are 150K~30M. It can be seen from the lower limit of the test frequency that the operating frequency of the switching Marine boost power supply is close to 150K, and the more difficult it is to deal with the conducted disturbance.

Diode loss
Diode rectification is used in traditional rectification, and Schottky diode rectification is generally used under low voltage output conditions. Compared with other rectifier diodes, Schottky diodes have the advantages of faster switching speed and lower forward voltage, but Schottky diodes The forward voltage drop of the diode is related to the size of the rectified output current. The larger the rectified output current is, the greater the forward voltage drop, which may be as high as 0.5~0.6V or more, and the reverse leakage current of the Schottky diode is larger. .

3. What special applications are required for the power switching frequency?

In some special cases, the circuit operation is more sensitive to the switching noise of the Marine boost power supply. Such as power carrier, wireless communication, wireless identification, etc. The Marine boost power supply requirements for power carrier applications are as follows.

power module

At present, the power carrier is mainly used for intelligent carrier in the home, remote meter reading system, and remote street lamp control system. The use range of the carrier frequency of power lines in my country is 9KHz ~ 500KHz, and the carrier bandwidth is 4KHz. The development of power carrier is very limited due to the change of power line impedance and the interference of power line noise. In order to increase the communication distance of the power carrier, we must move away from the power switching frequency of the circuit carrier unit. The carrier frequencies currently used in China are 115KHz and 132KHz. In this case, the switching frequency is around 60KHz for the Marine boost power supply.