Leadchip LC3406CB5TR Schematic [ru]
1.2A 1.5MHz 7V Synchronous Buck Converter
LC3406
GND
FB
IN
SW
240K
120K
10uF
LC3406
10uF
V
OUT
1.8V/1A
VIN
2.6V to 7V
1.8V/1A Step-Down Converter
2.2uH
EN
1
2
3
5
4
SOT23-5
FB
EN
SW
IN
G
GGZZ
DESCRIPTION
The LC3406 is a high-efficiency, DC-to-DC stepdown switching regulators, capable of delivering up
to 1.2A of output current. The device operates from
an input voltage range of 2.6V to 7.0V and provides
an output voltage from 0.6V to VIN, making the
LC3406 ideal for low voltage power conversions.
Running at a fixed frequency of 1.5MHz allows the
use of small external components, such as ceramic
input and output caps, as well as small inductors,
while still providing low output ripples. This low
noise output along with its excellent efficiency
achieved by the internal synchronous rectifier,
making LC3406 an ideal green replacement for large
power consuming linear regulators. Internal softstart control circuitry reduces inrush current. Shortcircuit and thermal-overload protection improves
design reliability.
LC3406 is housed in a SOT23-5 Package
FEATURES
High Efficiency: Up to 96%
Capable of Delivering 1.2A
1.5MHz Switching Frequency
No External Schottky Diode Needed
Low dropout 100% Duty operation
Internal Compensation and Soft-Start
Current Mode control
0.6V Reference for Low Output voltages
Logic Control Shutdown (IQ<1uA)
Thermal shutdown and UVLO
Available in SOT23-5
APPLICATIONS
Cellular phones
Digital Cameras
MP3 and MP4 players
Set top boxes
Wireless and DSL Modems
USB supplied Devices in Notebooks
Portable Devices
TYPICAL APPLICATION
www.leadchip.com 1 Your final power solution
PIN OUT & MARKING
LC3406
PART No.
PACKAGE
Tape&Reel
LC3406CB5TR
SOT23-5
3000/Reel
Parameter
Value
Max Input Voltage
7V
Max Operating Junction Temperature(Tj)
125C
Ambient Temperature(Ta)
-40C – 85C
Maximum Power Dissipation
SOT23-5
400mW
Storage Temperature(Ts)
-40C - 150C
Lead Temperature & Time
260C, 10S
ESD (HBM)
>2000V
Parameter
Value
Input Voltage Range
Max. 5.5V
Operating Junction Temperature(Tj)
-20C –125C
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VDD
Input Voltage Range
2.6 7.0
V
Vref
Feedback Voltage
Vin=5V
0.585
0.6
0.615
V
Ifb
Feedback Leakage current
0.1
0.4
uA
Iq
Quiescent Current
Active, Vfb=0.65, No Switching
35
uA
Shutdown
1
uA
LnReg
Line Regulation
Vin=2.7V to 5.5V
0.04
0.2
%/V
LdReg
Load Regulation
Iout=0.01 to 1A
0.1
0.2
%/A
Fsoc
Switching Frequency
1.5
MHz
RdsonP
PMOS Rdson
300
400
mohm
RdsonN
NMOS Rdson
220
300
mohm
Ilimit
Peak Current Limit
1.2
1.5 2 A
Iswlk
SW Leakage Current
Vout=5.5V, VSW=0 or 5.5V,
EN=0V
10
uA
Ienlk
EN Leakage Current
1
uA
Vh_en
EN Input High Voltage
1.5
V
Vl_en
EN Input Low Voltage
0.4
V
ORDERING INFORMATION
ABSOLUTE MAXIMUM RATING
Note: Exceed these limits to damage to the device. Exposure to absolute maximum rating conditions may affect
device reliability.
RECOMMENDED WORK CONDITIONS
ELECTRICAL CHARACTERISTICS
(VDD=5V, TA=25C)
www.leadchip.com 2 Your final power solution
LC3406
PIN #
NAME
DESCRIPTION
1
EN
Enable pin for the IC. Drive the pin to high to enable the part, and low to disable
2
GND
Ground
3
SW
Inductor connection. Connect an inductor between SW and the regulator output.
4
IN
Supply voltage.
5
FB
Feedback input. Connect an external resistor divider from the output to FB and
GND to set the output to a voltage between 0.6V and Vin
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0 100 200 300 400 500 600 700 800 900 1000
Efficiency (%)
Load Current (mA)
Efficiency VS Load Current,
Vout=1.8V
Vin=4.2V
Vin=3.6V
Vin=2.7V
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0 100 200 300 400 500 600 700 800 900 1000
Efficiency (%)
Load Current (mA)
Efficiency VS Load Current,
Vout=2.5V
Vin=4.2V
Vin=3.6V
Vin=2.7V
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0 100 200 300 400 500 600 700 800 900 1000
Efficiency (%)
Load Current (mA)
Efficiency VS Load Current,
Vout=1.2V
Vin=4.2V
Vin=3.6V
Vin=2.7V
PIN DESCRIPTION
ELECTRICAL PERFORMANCE
Tested under TA=25C, unless otherwise specified
www.leadchip.com 3 Your final power solution
Loading...