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Hello everyone, in this lesson we will talk about the PWM method in the power supply method

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The circuit structure of PWM power supply mode is relatively complicated,

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generally composed of PWM chip, field tube inductor and filter capacitor

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For example, the following circuit diagram

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It is composed of a PWM chip, two field tubes controlled by the chip,

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an energy storage inductor and a filter capacitor.

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The working process of the PWM power supply chip is that there is a power supply input first

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When the chip is powered, it gets a turn-on signal

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After the power supply is turned on, the chip can work

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It will control the conduction of the two field tubes in turn to output power

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The power supply will return to the chip through the circuit to detect and control the output voltage

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When the chip detection voltage is in the normal range, it will output a PG signal

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The PWM method has another structure, which is composed of PWM chips,

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inductors and filter capacitors, without field tubes

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So where did the management go?

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The field tube went inside the PWM chip

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The PWM power supply method using this structure is relatively simple, but its working process is still the same

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Power input first

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After the chip is powered, it gets a turn-on signal

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With the power supply, the chip can work after it is turned on, and it will output power supply

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This power supply will return to the chip to detect and adjust the output voltage

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After the voltage is stable, it will output a PG signal

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Although the circuit structure of the PWM power supply method is a little more complicated,

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its output power is very large, even reaching hundreds of A

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Therefore, most of the power supply methods used in the circuit are PWM power supply methods.