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Hello, everyone, today we are going to learn about the common pin definitions of PWM circuit

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First, let's look at the chip

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If we don't know the definitions of the pins,

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we don't know the meanings of them

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Let's look at the driver of the upper tube first.

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Common names are UGATE, DH, HDRV, DRVH, and so on

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So in this chip,

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the symbols DRVH on pin 21 and pin 10 are both upper tube drives

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Lower tube drive pins: LGATE, DL, LDRV, DRVL......

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In this chip, the pin 12 is DRVL, and the pin 19 is DRVL,

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both of which are lower tube drives

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The self-lift pin, which is the pin that powers the G pole of the upper tube

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Common names are BOOT, BST, VBST, BOOST, and so on

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In this chip, pins 9 and 22 VBST are both self-lift voltage pins,

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externally connected to a bootstrap capacitor

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FB, VSET, these are feedback regulation and voltage setting pins

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In this chip, both pins 2 and 5 are FBs, feedback regulation pins

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OUT, VOUT, VO, these are called output voltage detection input pins

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This corresponds to the pins 1 and pin 6 of the chip

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PHASE, SW, LX and LL are called phase pins

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They are connected to the front end of the inductor and can also be used to detect the current

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LL of pin 11 and pin 20 are phase pins

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CSP and CSN are called current detection pins, connected with the detection resistor

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This method of current detection is not used in this chip, so this chip does not have these two pins

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ILIM, TRIP, CS, OC, OCSET, these are called limit current setting pins,

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also called overcurrent protection threshold setting pins

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In this chip, the 14th TRIP2 and the 17th TRIP1 are the limit current setting pins

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SKIP, SKIPSEL, DEM, CCM, these are called working mode setting pins

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This chip does have these pins

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All right, let's continue to look

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TON, RT, RF, FSET, FS, these are called frequency setting pins

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The fourth pin here, TONSEL, is the frequency setting pin,

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which is used to set the pulse frequency of the PWM

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COMP is feedback compensation, used to correct the error of the feedback circuit

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There's no such pin here

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VSEN and ISEN, which are voltage detection and current detection pins,

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are commonly found in CPU power supply circuits

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Ok, these are the common pin definitions of PWM circuit