SC4524B
16V 2A Step-Down Switching Regulator
POWER MANAGEMENT
Features
Description
The SC4524B is a constant frequency peak current-mode
step-down switching regulator capable of producing 2A
output current from an input ranging from 3V to 16V. The
switching frequency of the SC4524B is programmable
up to 2MHz, allowing the use of small inductors and
ceramic capacitors for miniaturization, and high input/
output conversion ratio. The SC4524B is suitable for
next generation XDSL modems, high-definition TVs and
various point of load applications.
Peak current-mode PWM control employed in the
SC4524B achieves fast transient response with simple loop
compensation. Cycle-by-cycle current limiting and hiccup
overload protection reduces power dissipation during
output overload. Soft-start function reduces input start-
up current and prevents the output from overshooting
during power-up.
The SC4524B is available in SOIC-8 EDP package.
Wide input range: 3V to 16V
2A Output Current
200kHz to 2MHz Programmable Frequency
Precision 1V Feedback Voltage
Peak Current-Mode Control
Cycle-by-Cycle Current Limiting
Hiccup Overload Protection with Frequency Foldback
Soft-Start and Enable
Thermal Shutdown
Thermally Enhanced 8-pin SOIC Package
Fully RoHS and WEEE compliant
Applications
XDSL and Cable Modems
Set Top Boxes
Point of Load Applications
CPE Equipment
DSP Power Supplies
LCD and Plasma TVs
Typical Application Circuit
10V – 16V
C4
2.2mF
D1
1N4148
C1
0.1mF
L1
6.8mH
R4
102k
SS270 REV 4
Efficiency
V
IN
90
85
OUT
5V/2A
IN
BST
SW
80
Efficiency (%)
75
70
65
60
55
50
45
40
V
IN
= 12V
SS/EN
SC4524B
FB
COMP
C7
10nF
R7
30.1k
C5
1nF
ROSC
GND
D2
20BQ030
R6
25.5k
C2
22mF
C8
10pF
R5
18.2k
L1: Wurth 744 778 9006
C2: Murata GRM31CR60J226K
C4: Murata GRM31CR61E225K
0
0.5
1
1.5
2
Load Current (A)
Figure 1. 1MHz 10V-16V to 5V/2A Step-down Converter
November 1, 2007
1
SEMTECH [ SEMTECH CORPORATION ]
