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SC1548

Linear Fet Controller

POWER MANAGEMENT

Revision 1, January 2001

Typical Application Circuit

The SC1548 is a power supply controller designed to

provide a simple single regulated power supply with over

current protection. It is part of Semtech’s SmartLDO™

family of products. The SC1548 can provide a 1.818V

power supply for the I/O plane or 1.515V for GTL+ / AGP

from either 3.3V or 2.5V. An adjustable option allows

generation and control of any voltage from 1.263V up to

5V.

SC1548 features include tight output voltage regulation,

an enable control and over current protection. Over

current protection is provided by feedback to the sense

pin. If the output drops below 50% of the nominal

output voltage (typical) for greater than 4ms (typical), the

output will be shut down.

The SC1548 is available in a tiny 5-pin SOT-23 surface

mount package.

temperature

options available

1.818V OUT

3.3V IN

12V IN

ENABLE

Q1

IRL530N

C4

0.1uF

+

C1

100uF

+

C2

100uF

+

C3

22uF

U1

SC1548CSK-1.8

1

2

3

4

5

SNS

GND

DRV

IN

EN

Adjustable Output Voltage Version

2.5V OUT

3.3V IN

12V IN

ENABLE

Q1

IRL530N

C4

0.1uF

+

C1

100uF

+

C2

100uF

+

C3

22uF

R1

97.6

R2

100

U1

SC1548CSK

1

2

3

4

5

ADJ

GND

DRV

IN

EN

Fixed Output Voltage Versions

Description

Features

Applications