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In this lesson, we talk about the circuit diagram related to the electricity leakage

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We know that the circuit related to electricity leakage is mainly divided into two parts

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The first one is the circuit of the positive pole of the battery,

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and the second is the main power supply circuit

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Let's look at the main power supply first

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What components and chips are its circuit connected to?

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Let's take a look at the circuit diagram

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We open Xinzhizao maintenance query system

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For example, we open the mainboard of Xiaomi 10

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How do we find its main power supply in the circuit diagram?

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We learned earlier that its battery connector will go to the charging chip,

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which is U5200

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So, what role does the charging chip play in the power-on circuit?

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It is to turn on the positive electrode of the battery through the internal MOS tube,

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power supply comes out from PIN 78

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Since the source of the main power supply is here,

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let's take a look at which components and chips are connected to the main power supply

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We see that it leads to the chip U5200,

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and of course it also leads to these five components

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In this position we see five small components,

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and one chip is the charging chip

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Of course, this main power supply will lead to many places

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On this page, these six components are directly related

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Okay, let's continue to double click on the name and see where it goes

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It leads to the chip U6001,

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and there are two filter capacitors next to it

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It leads to chip U6005 and there are two capacitors

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Let's keep looking, here is a capacitor

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It leads to a socket J6501 and a capacitor

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It leads to the 3rd, 5th and 13th pins of the chip U7302

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the capacitors C7362 and C7363

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This is not what we are looking for,

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because there is an extra DIV behind it

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It leads to the socket J0196 and this capacitor

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Here it is through a zero ohm resistor

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And here, through the inductor,

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it leads to chip U0900, here is a capacitor C0907

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Here it leads to the chip U1801_4

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here it leads to the chip U1801-5,

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and it has three capacitors on this line

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Here it leads to the chip U1902,

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and there are two capacitors are connected at the same time

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It leads to the chip U1903,

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and the two capacitors are connected at the same time

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Here it leads to the chip U2001,

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and three capacitors are connected at the same time

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Here, it leads to the chip U2105 through a zero-ohm resistor,

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as well as two capacitors C2111 and C2112

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Here it is connected to the chip U2501 through a 0-ohm resistor,

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there are five capacitors on it

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Here it leads to the chip U2500 and five capacitors

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I won't look for other lines one by one

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As long as this code name is the main power supply,

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any chip or capacitor it leads to is associated with it

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We found that VPH_PWR leads to a lot of components

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Let's summarize,

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a problem with a component connected to this line may cause the electricity leakage

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Okay, that's it for this lesson