1

00:00:01,166 --> 00:00:06,366

Hello everyone, today we continue to learn the pin definition of the CPU power supply chip of

2

00:00:06,366 --> 00:00:08,433

the Wistron 15221 mainboard.

3

00:00:09,400 --> 00:00:16,133

It can be found from the physical map that the position number of the CPU power supply chip is PU4601,

4

00:00:16,133 --> 00:00:19,400

and the actual model is ISL95829

5

00:00:25,533 --> 00:00:30,833

It controls 5 DRMOS power supply chips at the same time

6

00:00:31,500 --> 00:00:38,233

The leftmost road is to supply power to the VCCSA of the CPU

7

00:00:41,200 --> 00:00:45,466

The two roads in the middle are the core power supply of the CPU

8

00:00:47,866 --> 00:00:54,600

The two roads on the far side are its integrated display power supply VCCGT

9

00:00:54,866 --> 00:00:58,733

They use this kind of d r moss power supply chip

10

00:00:59,500 --> 00:01:06,533

This DRMOS power supply chip integrates the upper tube, the lower tube, and the driver

11

00:01:07,933 --> 00:01:13,033

Ok, let's take a look at the pin definition of this chip

12

00:01:15,600 --> 00:01:22,533

Search component position number "PU4601"

13

00:01:26,533 --> 00:01:33,233

Its 5 pins are grounded through five resistors respectively

14

00:01:34,733 --> 00:01:38,166

In the circuit diagram, some information is given here

15

00:01:38,600 --> 00:01:44,066

The pin of PROG1 is grounded through a 110K resistor

16

00:01:44,200 --> 00:01:47,766

This pin is the VBOOT voltage setting pin

17

00:01:49,133 --> 00:01:52,200

The current voltage of VBOOT is 0V

18

00:01:54,033 --> 00:01:58,100

PROG2 is grounded through a 34K resistor, which is used to set the maximum output current of

19

00:01:58,933 --> 00:02:01,233

Group A power supply

20

00:02:04,000 --> 00:02:07,866

PROG3 is grounded through a 16K resistor,

21

00:02:09,233 --> 00:02:15,066

which is used to set the maximum output current of group B power supply

22

00:02:15,966 --> 00:02:21,966

PROG4 is the frequency setting for group A and group B power supply

23

00:02:23,733 --> 00:02:30,000

PROG5 is the limit current setting and frequency setting of group C power supply

24

00:02:34,466 --> 00:02:40,533

The power supply of group a, group b and group c we mentioned here

25

00:02:41,900 --> 00:02:48,733

They refer to the core power supply of group A, the integrated display power supply of group B,

26

00:02:51,300 --> 00:02:54,300

and the VCCSA power supply of group C

27

00:02:55,766 --> 00:03:00,233

The pin definitions of these three groups of power supplies are basically the same

28

00:03:00,933 --> 00:03:04,100

This VIN is the main power supply of the chip, provided by the common point voltage,

29

00:03:04,466 --> 00:03:09,133

and the voltage value is 19V

30

00:03:10,066 --> 00:03:15,366

VCC is also the working voltage of the chip, it is the power supply of 5V

31

00:03:15,866 --> 00:03:19,066

When we measure the working condition of this pin

32

00:03:20,233 --> 00:03:26,933

Try not to measure directly on the chip pins, so as not to short-circuit and burn the chip

33

00:03:27,200 --> 00:03:31,600

We can measure on pin externally connected components

34

00:03:32,833 --> 00:03:40,033

The 43rd, 44th, and 45th pins are SVID pins, respectively SVID_DATA,

35

00:03:40,700 --> 00:03:45,733

SVID_CLK and a prompt signal, ALERT#

36

00:03:49,733 --> 00:03:52,633

These SVID signals are connected to the CPU

37

00:03:53,100 --> 00:04:01,000

After the CPU meets the working conditions, it will send the SVID waveform to the power chip

38

00:04:01,533 --> 00:04:04,600

Pin 46 is VR_HOT#

39

00:04:04,966 --> 00:04:08,900

This is an overheating indication signal output,

40

00:04:09,300 --> 00:04:13,333

usually sent to the PROCHOT# pin of the CPU

41

00:04:13,633 --> 00:04:15,700

This signal is active low

42

00:04:16,133 --> 00:04:19,933

Low level indicates that the CPU power supply circuit is overheated

43

00:04:20,233 --> 00:04:22,933

In this chip, the power supply of Group B has an NTC pin

44

00:04:23,733 --> 00:04:25,800

Group B power supply has 1 NTC pin

45

00:04:27,800 --> 00:04:31,166

These two NTC pins are connected to the thermal group

46

00:04:31,600 --> 00:04:36,866

They are respectively used to detect the power supply temperature of the integrated display and

47

00:04:37,466 --> 00:04:40,466

the power supply temperature of the core power supply

48

00:04:41,233 --> 00:04:44,233

This thermistor is usually placed next to the inductor

49

00:04:48,500 --> 00:04:55,366

For example, the thermistor of this integrated display power supply is called PR4637

50

00:04:58,633 --> 00:05:01,266

In real life, this small component is the PR4237

51

00:05:01,900 --> 00:05:08,266

When NTC_B/NTC_A detects that the temperature of the power supply circuit is too high

52

00:05:08,600 --> 00:05:16,166

The CPU power supply chip will pull down the VR_HOT# pin to notify the CPU power supply circuit of overheating

53

00:05:18,500 --> 00:05:23,733

When the CPU receives a low-level VR_HOT#,

54

00:05:23,900 --> 00:05:29,566

the CPU will also communicate with the EC to adjust the fan speed

55

00:05:30,100 --> 00:05:34,933

through the EC to achieve the purpose of cooling

56

00:05:35,300 --> 00:05:39,300

At the same time, the CPU itself will reduce the frequency to work,

57

00:05:39,666 --> 00:05:42,066

so the performance of the system will be affected,

58

00:05:42,533 --> 00:05:46,100

it will become very slow, and the operation will be very stuck.

59

00:05:46,766 --> 00:05:49,733

VR_READY means that the chip is ready

60

00:05:53,466 --> 00:05:57,066

Usually we use this signal as a PG signal

61

00:05:57,866 --> 00:06:02,066

Pin 48 VR_ENABLE is the enable signal

62

00:06:02,766 --> 00:06:08,833

Pin 1 PSYS, usually the system power information provided by the charging chip

63

00:06:13,966 --> 00:06:21,500

IMON_B refers to the current monitoring output of Group B (this pin is generally not used)

64

00:06:24,033 --> 00:06:27,166

COMP_B is the compensation pin

65

00:06:28,033 --> 00:06:33,900

This is the compensation at the output of the on-chip comparator

66

00:06:34,400 --> 00:06:39,566

External grounding through resistors and capacitors is used

67

00:06:40,066 --> 00:06:43,733

to correct the error at the output of the internal comparator

68

00:06:44,466 --> 00:06:48,133

The two pins FB_B and RTN_B are voltage detection pins,

69

00:06:49,966 --> 00:06:53,666

which detect whether the power supply of group B is normal

70

00:06:54,900 --> 00:07:00,600

They are respectively connected to the set display power supply pin and ground pin inside the CPU.

71

00:07:03,966 --> 00:07:07,600

Used to detect whether VCCGT is normal

72

00:07:10,566 --> 00:07:14,533

This kind of voltage feedback, we call it remote detection

73

00:07:14,533 --> 00:07:17,600

It is not directly detected from the back end of the pole,

74

00:07:17,900 --> 00:07:23,700

but directly fed back from the inside of the CPU to detect the actual voltage received by the CPU

75

00:07:27,700 --> 00:07:30,966

Next are ISUMP_B and ISUMN_B

76

00:07:33,200 --> 00:07:36,466

This is the total current detection pin of the integrated display power supply

77

00:07:36,700 --> 00:07:43,366

ISEN1_B, ISEN2_B This is the current detection of the first phase and the second phase set display power supply

78

00:07:45,100 --> 00:07:49,866

This current sense pin is usually connected to the front and back of the inductor

79

00:07:51,000 --> 00:07:55,166

The front end of the inductor is PWR_I2_SEN1_P

80

00:07:58,500 --> 00:08:03,900

The back end is called PWR_I2_SEN1_N, which is used to detect the current flowing through the inductor

81

00:08:05,300 --> 00:08:10,833

The PU4601 main chip needs to detect the output current of each phase inductor

82

00:08:12,533 --> 00:08:15,633

Its purpose is to achieve equal flow

83

00:08:16,200 --> 00:08:19,900

For example, this integrated display power supply needs to use a current of 90A

84

00:08:21,666 --> 00:08:25,966

On average, each phase needs to output a current of 45A

85

00:08:26,766 --> 00:08:29,233

If the current detection circuit is not normal,

86

00:08:29,600 --> 00:08:34,733

it will cause the output current of the two-phase power supply to be uneven and unbalanced.

87

00:08:36,133 --> 00:08:42,033

In this case, the phase circuit with a large output current is easy to burn out.

88

00:08:43,333 --> 00:08:50,766

Therefore, the main purpose of current detection is to make the output current of each inductor consistent

89

00:08:51,066 --> 00:08:56,300

This FCCM is the turn-on signal sent to the DMOS chip, active high

90

00:08:56,800 --> 00:09:03,133

The pulse signals sent by PWM1 and PWM2 will also be sent to the DRMOS chip to drive the DRMOS chip

91

00:09:04,366 --> 00:09:11,866

to work normally and control the generation of power supply output

92

00:09:13,800 --> 00:09:19,300

PWM1_B came to the PWM pin of this DRmos chip

93

00:09:20,600 --> 00:09:27,633

FCCM is equivalent to the open signal, and it also comes to the FCCM pin of this DRMOS chip

94

00:09:30,233 --> 00:09:33,766

And this FCCM is shared by two chips

95

00:09:34,800 --> 00:09:40,900

Next, look at the chip pin definition of this DRMOS

96

00:09:43,166 --> 00:09:46,666

VIN is the power supply of the upper tube D pole inside the chip

97

00:09:47,966 --> 00:09:52,900

PVCC and VCC are the working voltage of this chip

98

00:09:53,100 --> 00:09:55,966

VBOOT is the bootstrap boost pin

99

00:09:56,666 --> 00:10:01,466

Externally connected bootstrap boost capacitor, connected to phase pin

100

00:10:02,100 --> 00:10:08,433

Both this VSWH and this PHASE refer to the inductance front end (phase pin)

101

00:10:09,300 --> 00:10:12,500

GND means ground

102

00:10:14,166 --> 00:10:20,566

The rest is to connect the PWM pulse and FCCM of the main chip

103

00:10:21,666 --> 00:10:26,633

During normal operation, this FCCM is a high-level turn-on signal,

104

00:10:26,633 --> 00:10:29,166

and this PWM is a pulse

105

00:10:30,866 --> 00:10:34,933

If the PWM does not send pulses, the chip will not work

106

00:10:35,266 --> 00:10:39,366

The pin definitions of each DRMOS chip are the same

107

00:10:41,733 --> 00:10:44,433

We can also see it in real

108

00:10:44,633 --> 00:10:49,433

FCCM is equivalent to the open signal, connected to two chips

109

00:10:49,633 --> 00:10:53,366

Then PWM1 will generally be connected to one of the chips

110

00:10:53,533 --> 00:10:58,966

PWM2 will be connected to another chip to drive the two chips to work normally

111

00:11:00,600 --> 00:11:03,733

Voltage Sensing and Current Sensing

112

00:11:04,100 --> 00:11:09,933

Current detection is to directly detect the front end

113

00:11:09,933 --> 00:11:13,133

and back end of the inductor through the chip current detection pin,

114

00:11:13,766 --> 00:11:17,600

and detect the output current of the inductor

115

00:11:18,500 --> 00:11:23,200

For example, the voltage detection of this integrated display power supply

116

00:11:23,533 --> 00:11:29,133

The set connected to the CPU internally through FB is the power supply pin

117

00:11:29,366 --> 00:11:34,933

There is also an RTN pin which is connected to ground inside the CPU

118

00:11:35,433 --> 00:11:38,533

These two pins are voltage feedback pins

119

00:11:38,766 --> 00:11:44,266

It is not the same as the voltage feedback of other circuits

120

00:11:46,166 --> 00:11:52,800

The feedback of other circuits is to divide the voltage from the rear end of the pole through

121

00:11:52,800 --> 00:11:54,966

connecting resistors in series,

122

00:11:55,200 --> 00:12:00,466

and the sampling of the divided voltage is fed back to the chip to adjust the PWM output.

123

00:12:01,666 --> 00:12:05,766

But the feedback of the CPU power supply is all from the internal feedback of the CPU.

124

00:12:08,033 --> 00:12:11,100

Because the CPU power supply is multi-phase power supply

125

00:12:11,666 --> 00:12:15,566

Therefore, it is necessary to ensure that the current of each phase is consistent.

126

00:12:15,900 --> 00:12:18,866

So its current detection circuit is more precise

127

00:12:20,633 --> 00:12:26,200

This inductor is a very unreliable component as a current detection component.

128

00:12:26,466 --> 00:12:31,833

It will change with the working frequency and working temperature

129

00:12:32,266 --> 00:12:38,466

So we can see some compensation components in this current sense pin

130

00:12:39,100 --> 00:12:44,200

Here you can see some thermistor as its temperature compensation

131

00:12:44,200 --> 00:12:48,500

and some other precision resistors as some of its impedance compensation

132

00:12:49,233 --> 00:12:55,266

This is to correct its error and try to make the current detection more accurate

133

00:12:55,633 --> 00:13:03,200

The pin definition of other group A power supply and C group power supply is the same as that of group B

134

00:13:04,966 --> 00:13:06,966

Here we will not repeat the introduction

135

00:13:08,533 --> 00:13:11,400

Ok, this is the pin definition of the CPU power supply chip