SC1548_04 Datasheet, PDF (1/14 Pages) Semtech Corporation – Linear FET Controller

SC1548
Linear FET Controller
POWER MANAGEMENT
Description
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.
Features
‹ ± 2.5% output accuracy over line, load and
temperature
‹ 1.515V, 1.818V and adjustable output voltage
options available
‹ Enable control
‹ Over current protection
‹ 5-pin SOT-23 package
Applications
‹ Motherboards
‹ Graphics cards
‹ Microcontrollers
‹ Simple power supplies
The SC1548 is available in a tiny 5-pin SOT-23 surface
mount package.
Typical Application Circuit
Fixed Output Voltage Versions
1.818V OUT
Q1
IRL530N
+
C1
100uF
+
C2
100uF
+
C3
22uF
3.3V IN
12V IN
U1
1 _{SNS EN} 5
2 _GND
3 _{DRV IN} 4
SC1548CSK-1.8
ENABLE
C4
0.1uF
Adjustable Output Voltage Version
2.5V OUT
R1
97.6
+
C1
100uF
Q1
IRL530N
+
C2
100uF
+
C3
22uF
R2
100
3.3V IN
12V IN
U1
1 _{ADJ EN} 5
2 _GND
3 _{DRV IN} 4
SC1548CSK
ENABLE
C4
0.1uF
Revision: November 10, 2004
1
www.semtech.com