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Hello everyone, today we are going to learn what components PWM power supply mode consists of

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First of all, PWM power supply mode needs four components,

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control chip, MOS tube, inductor and filter capacitor

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In real objects, each inductor represents a PWM circuit

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The filter capacitor is at the back end of the inductor,

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and the upper and lower tubes are at the front end

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The D pole of the upper tube is connected to the common point voltage,

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the S pole of the upper tube is connected to the front end of the inductor,

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and the D pole of the lower tube is connected

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The S pole of the lower tube is grounded

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The G poles of the upper and lower tubes are controlled by the control chip

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The pin that the chip controls the upper tube G pole is called the upper tube drive, commonly known as UGATE

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The pin that the chip controls the G pole of the lower tube is called the lower tube drive, LGATE

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The end where the inductor is connected to the MOS tube is called the front end of the inductor

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The end connected to the capacitor is called the back end of the inductor, which is the voltage output end

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The front end of the inductor is connected to the S pole of the upper tube and the D pole of the lower tube,

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and it also returns to the phase pin of the control chip

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Ok, this is the basic architecture of PWM power supply

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In a real circuit, the front end is connected to the MOS tube,

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and the back end is the inductor

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Use a multimeter to measure the 1 pin of two MOS tubes

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If the pin 1, 2, or 3 of one of the two MOS tubes is connected to the ground,

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it means that this is the lower tube

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Because pin 1, 2, or 3 of the upper tube is not grounded

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The multimeter is set to the diode gear, the red pen is grounded,

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and the black pen is used to measure pin 1, 2, or 3 of the two MOS tubes

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The one that communicates with the ground is the lower tube,

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that is, the S-pole of the MOS tube communicates with the ground, which means that it is the lower tube

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Next, let's take a look at the DrMOS power supply

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In this way, the upper and lower tubes are integrated into the chip

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So it only consists of control chip and inductor/ capacitor, no MOS tube

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That's how it works in real circuit

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This is the DrMOS power supply, the chip is connected to the inductor,

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inductor at the back of the filter capacitor on the mainboard

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The end of the inductor connected to the capacitor is called the back end of the inductor

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This end of the inductively connected chip is called the inductor front end, and this is also called the phase pin

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Okay, so this is the common PWM power supply

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So that's it for this lesson