11

 2007 Semtech Corp.

www.semtech.com

POWER MANAGEMENT

SC4521

Application Information (Cont.)

Design Example 1: 5V to 1V at 2A

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C1

0.22u

SC4521

IN

2

SW

3

EN

5

FB

6

COMP

7

SS

8

R1

2.49k

R3

20k

C4

18n

Co

470u

D2

L1

3.9uH

C5

560p

C3

10u

D1

R0

0

R2

10k

Css

100n

C1

0.22u

SC4521

IN

2

SW

3

EN

5

FB

6

COMP

7

SS

8

R1

2.49k

R3

20k

C4

18n

Co

470u

D2

L1

3.9uH

C5

560p

C3

10u

D1

R0

0

R2

10k

Css

100n

Note: The bottom pad needs a big copper area to remove the heat.