9

 2005 Semtech Corp.

www.semtech.com

POWER MANAGEMENT

SC1408

Typical Application Circuit (Cont.)

Fig.1: Typical Application - Boost Configuration

D1

B130T

L1 22uH

C9

See Text

U1

SC1408CS

8

1

2

3

4

5

6

7

ISENSE

GATE

BST

FB

EN

REF

AGND

GND

+

C3

100uF

+

C8

100uF

R3

See Table

Vin to 16.5V OUT

R2

0.1Ohm

Q1

IRLR024N

R4

10.0k

C5

0.1uF

+

C2

100uF

1.8V-16.5V IN

Coilcraft DO3316P-223

Fig.2: Typical Application - Buck/Boost (SEPIC) Configuration

D1

B130T

R2

0.1Ohm

R3

See Table

+

C8

100uF

D2 1N4148

Q1

IRLL3303

L1A 22uH

1

2

R4

10.0k

C9

See Text

0V TO (16.5V-Vin) OUT

L1B

22uH

4

3

C5

0.1uF

1.8V TO 5V IN

U1

SC1408CS

8

1

2

3

4

5

6

7

ISENSE

GATE

BST

FB

EN

REF

AGND

GND

C4

0.1uF

+

C2

100uF

+

C3

100uF

L1A/L1B IS COUPLED INDUCTOR

PULSE PE-53718 OR

EQUIVALENT

+

C1

100uF