8

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FAN5182 Rev. 1.0.1

Application Circuit

Figure 5. 1.8V, 55A Application Circuit

( Consult Fairchild Sales for an updated version of the Application Circuit )

12 V

ENABLE

POWER

GOOD

RLIM

287k

Ω

RPH1

140k

Ω

RR

332k

Ω

Q1

FDD6296

Q2

FDD8896

Q3

FDD6296

Q5

FDD6296

Q4

FDD8896

Q6

FDD8896

CDLY

68nF

1.8 V

55A

1200

µF / 6.3V x 5

15m

Ω ESR (each)

+

L2

600nH / 1.4m

Ω

L3

600nH / 1.4m

Ω

L4

600nH / 1.4m

Ω

L1

1

µH

RT

255k

Ω

C8

100nF

C17

+

C21

U3

FAN5009

1

2

3

8

7

6

4

5

BOOT

PWM

OD

VCC

HDRV

SW

PGND

LDRV

C7

1

µF

C4

100nF

C3

1

µF

C5

4.7

µF

C9

4.7

µF

C13

4.7

µF

U2

FAN5009

1

2

3

8

7

6

4

5

BOOT

PWM

OD

VCC

HDRV

SW

PGND

LDRV

C12

100nF

U4

FAN5009

U1

FAN5182

1

2

3

8

7

6

4

5

BOOT

PWM

OD

VCC

HDRV

SW

PGND

LDRV

C11

1

µF

C15

1

µF

R4

10

Ω

RA

6.04k

Ω

CFB

100pF

CA

1.2nF

CCS

5.6nF

C2

2700

µF

16V

C1

2700

µF

16V

+

+

4.7

µFx10

6.3V

MLCC

C14

2.2nF

C10

2.2nF

C6

2.2nF

R3

2.2

Ω

R2

2.2

Ω

R1

2.2

Ω

D1

(optional)

D2

(optional)

D3

(optional)

RB2

1.24k

Ω

RB1

1.00k

Ω

RCS

100k

Ω

RPH2

140k

Ω

RDLY

261k

Ω

RSW1

*

RSW3

*

RSW2

*

RPH3

140k

Ω

VCC

FBRTN

FB

COMP

PWRGD

EN

DELAY

RT

RAMPADJ

ILIMIT

PWM1

PWM2

PWM3

SW1

SW2

SW3

GND

CSCOMP

CSSUM

CSREF

1

2

3

20

19

18

4

8

10

5

6

7

13

16

15

14

9

11

12

17

RTN