14

 2006 Semtech Corp.

www.semtech.com

SC4601

POWER MANAGEMENT

Applications Information - (Cont.)

Design Example 2: 5V to 0.8V ~ 1.8V @ 0.4A ~ 1.8A Xenpak application with SC4601.

Figure 7. Schematic for Xenpak application with SC4601

U1

S C 4601

VCC

1

SYNC/SLEEP

2

COMP

3

VSENSE

4

FS

5

ISET

6

PHASE

7

GND

8

NDRV

9

PDRV

10

R15 1

U2

FDS8928A

Gn

2

Gp

4

Dn1

5

Dn2

6

Dp1

7

Dp2

8

C3

4.7u

C7

150u

C14

33n

R6

1.0

R5

1.0

R16

750

R9

C10

10u

C11

10u

R10

1.47k

R0 30.1K

C1

1.5n

C2

33n

R1

1.58K

R3

L1

4.7u

From outside

C4

10u

C9

33n

R8

17.8

R7

953

JA

5V

1

5V

2

GND

3

GND

4

GND

5

APS-SET

6

APS-SENSE

7

GND

8

APS-OUT

9

APS-OUT

10

U1

S C 4601

VCC

1

SYNC/SLEEP

2

COMP

3

VSENSE

4

FS

5

ISET

6

PHASE

7

GND

8

NDRV

9

PDRV

10

R15 1

U2

FDS8928A

Gn

2

Gp

4

Dn1

5

Dn2

6

Dp1

7

Dp2

8

C3

4.7u

C7

150u

C14

33n

R6

1.0

R5

1.0

R16

750

R9

C10

10u

C11

10u

R10

1.47k

R0 30.1K

C1

1.5n

C2

33n

R1

1.58K

R3

L1

4.7u

From outside

C4

10u

C9

33n

R8

17.8

R7

953

JA

5V

1

5V

2

GND

3

GND

4

GND

5

APS-SET

6

APS-SENSE

7

GND

8

APS-OUT

9

APS-OUT

10

Vin = 3.3V

VCC

1

SY NC/SLEEP

2

COMP

3

VSENSE

4

FS

5

ISET

6

PHASE

7

GND

8

NDRV

9

PDRV

10

U1

SC4601

R15

1

C3

4.7u

R2

3.32k

C7

150u

C14

33n

R6

1.0

R5

1.0

R9

3.09k

M2

C10

22u

C11

22u

C12

22u

C13

22u

R11

100

ON/OFF

R10

100

TRIM

Vo = 1.5V/6A

C4

22u

R0 30.1K

C1

470p

C2

6.8n

R1

5.1K

R3

3.65K

L1

1.6u

C9

5.6n

R8

102

M1

R7

2.7k

Figure 6. Schematic for 3.3V/1.5V @ 6A application