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L6919C

DEMO BOARD ENHANCEMENTS: 1.200V / 52A CPU Power Supply

Considering the same application schematic, minor changes can be done to achieve the 52A thermal output

current required by AMD Hammer processor core. Part list has been modified as follow:

Part List

R1, R2, R20,R21

Not Mounted

SMD 0805

R3, R4, R5, R6

1.5k

1%

SMD 0805

R7

1k

1%

SMD 0805

R8

1.8k

SMD 0805

R9

47k

1%

SMD 0805

R10

510

SMD 0805

R11

82

SMD 0805

R12 to R19

0

SMD 0805

C1

Not Mounted

SMD 0805

C2

10n

SMD 0805

C3, C4

100n

SMD 0805

C5, C6, C7, C8

1

µ

Ceramic

SMD 1206

C9, C10

10

µ or 22µ / 16V

TDK Multilayer Ceramic SMD 1206

C11 to C13

1800

µ / 16V

Rubycon MBZ

Radial 10x23

C14 to C18

2200

µ / 6.3V

Rubycon MBZ

Radial 10x20

C24

100n

SMD 0805

L1, L2

0.8

µ

77121 - 4Turns

U1

L6919C

STMicroelectronics

SO28

Q1, Q1a, Q3, Q3a

SUB85N03-04P

Vishay-Siliconix

D

Q2, Q4

SUB70N03-09BP

Vishay-Siliconix

D

D1, D2

STPS340U

STMicroelectronics

SMB

D3, D4

1N4148

STMicroelectronics

SOT23

S0,S4

Short

S1,S2,S3

Open

STATIC PERFORMANCES

Figure 27 shows the demo board measured efficiency versus load current in steady state conditions without air-

flow at ambient temperature.

Figure 27. System Efficiency

40

45

50

55

60

65

70

75

80

85

90

0

5

10

15

20

25

30

35

40

45

50

55

60

Output Current [A]