1

00:00:00,333 --> 00:00:07,033

Hello everyone, today we will introduce the CD3217 chip in the Apple A2337 circuit

2

00:00:10,533 --> 00:00:14,500

CD3217 is in this position in the actual mianboard

3

00:00:15,633 --> 00:00:20,933

Its full name is CD321712, it is a USBC controller

4

00:00:23,966 --> 00:00:30,233

There are two CD3217 chips here, each chip is responsible for a Type-C interface

5

00:00:32,733 --> 00:00:35,800

The cable of the Type-C interface is at this position

6

00:00:37,133 --> 00:00:39,000

The cable is plugged in here

7

00:00:41,333 --> 00:00:43,666

There are two Thunderbolt chips next to it,

8

00:00:43,833 --> 00:00:47,366

which are responsible for the data communication of the Type-C interface

9

00:00:50,666 --> 00:00:56,000

After inserting the adapter, the adapter mainly communicates with CD3217

10

00:00:59,466 --> 00:01:03,100

If this chip is damaged, it will cause the adapter not to boost

11

00:01:04,066 --> 00:01:08,566

When we replace, we also need to find the same type of chip to replace

12

00:01:10,566 --> 00:01:16,166

The position numbers of the CD3217 chip in the circuit are UF400 and UF500

13

00:01:22,600 --> 00:01:26,633

The slot position number of the Type-C cable is JF600

14

00:01:29,866 --> 00:01:31,666

Let's look at the circuit diagram

15

00:01:32,533 --> 00:01:36,166

This is the pin definition of the JF600 interface

16

00:01:37,800 --> 00:01:41,433

Pins 57 and 58 of the interface are power supplies

17

00:01:48,200 --> 00:01:54,000

After inserting the adapter, the power supply of the adapter is sent from pins 57 and 58,

18

00:01:54,333 --> 00:01:58,033

and the external name is PPVBUS_USBC0

19

00:02:00,366 --> 00:02:04,066

The power supply is sent to the VBUS pin of the UF400 chip

20

00:02:07,900 --> 00:02:12,266

The adapter also has a CC bus, which is CC1 and CC2 here

21

00:02:15,733 --> 00:02:19,033

CC1 and CC2 are connected to the Type-C interface

22

00:02:21,266 --> 00:02:24,133

Here it is, USBC0_CC2

23

00:02:32,866 --> 00:02:35,066

Let's take a look at its boost process

24

00:02:35,800 --> 00:02:37,400

When the adapter is inserted, the CC bus of the adapter will be pulled down

25

00:02:38,166 --> 00:02:43,700

by the internal resistance of the CD3217 chip

26

00:02:45,900 --> 00:02:49,533

Then the adapter will output a 5V power supply before boosting

27

00:02:51,133 --> 00:02:55,300

If we cut off the communication between the adapter and the CD3217,

28

00:02:59,266 --> 00:03:02,066

so that the adapter cannot communicate with the chip,

29

00:03:04,166 --> 00:03:07,400

the adapter will not be able to output the 5V power supply

30

00:03:12,166 --> 00:03:14,700

When the adapter outputs 5V power supply,

31

00:03:15,133 --> 00:03:19,166

this power supply will be supplied to the VBUS pin of CD3217

32

00:03:22,266 --> 00:03:28,500

CD3217 will output 3.3V LDO linear to provide power for external chips

33

00:03:31,600 --> 00:03:36,933

At the same time, CD3217 will internally control the conduction of the MOS tube,

34

00:03:37,400 --> 00:03:41,866

convert the VBUS power supply, and output it from the PPHV pin

35

00:03:45,933 --> 00:03:50,833

It converts the 5V of the adapter to provide power to the common point circuit behind

36

00:03:52,900 --> 00:03:56,400

Well, this is the main function of the CD3217 chip