SC2308A Datasheet, PDF (1/17 Pages) Semtech Corporation – 600kHz Step-Up Switching Regulator with 2.2A, 45V Switch

POWER MANAGEMENT
Features
 Input Voltage Range: 2.6V to 20V
 Boost and SEPIC Topologies
 Up to 40V Output in Boost Topology
 Integrated 2.2A/45V Switch
 600kHz Constant Switching Frequency
 Current-Mode Control Eases Compensation
 Cycle-by-Cycle Current-Limiting
 Internal Soft-Start
 Thermal Shutdown Protection
 Low Shutdown Current (<1µA)
 8-Pin SO Lead-Free Package
 Fully WEEE and RoHS Compliant
Applications
 Telecommunication Equipment
 Point of Load DC-DC Converters
 Portable Devices
SC2308A
600kHz Step-Up Switching
Regulator with 2.2A, 45V Switch
Description
The SC2308A is a 600kHz current-mode switching regulator
with an integrated low-side 2.2A power transistor. The oper-
ating supply voltage of the SC2308A ranges from that of a
single Li-ion cell to various PC board power supplies. The
internal switch is rated at 45V, making the device suitable
for high voltage boost and SEPIC applications. The SC2308A
shuts down to less than 1µA of supply current.
The SC2308A uses peak current-mode PWM control for ease
of loop compensation and excellent transient response.
Cycle-by-cycle current limiting lowers power transistor
dissipation. An internal soft-start timer prevents output
overshoot and limits the input current during start-up.
Thermal shutdown prevents the chip from overheating.
Typical Application Circuit
V_IN
L
D₁
5V
10µH
SS22
IN
SW
OFF ON
C₁
4.7µF
EN SC2308A
COMP
FB
GND
C₄
470pF
R₃
200k
R₁
100k
C₃
22µF
V_OUT
12V, 0.8A
C₂
22µF
R₂
11.3k
L: Coilcraft DO3316P103
D₁: ON SS22
C₁: Murata GRM31CR61A475K
C₂,C₃: Murata GRM31CR61C226K
Figure 1. 5V to 12V Step-Up Converter
Rev. 2.0
100
90
80
70
60
50
40
30
20
0
E fficiency vs Load C urrent
V_OUT = 12V
V _IN = 5V
200
400
600
800
Load Current (mA)