SGM6232
2A, 38V, 1.4MHz Step-Down Converter
GENERAL DESCRIPTION
The SGM6232 is a current-mode step-down regulator
with an internal power MOSFET. This device achieves
2A continuous output current over a wide input supply
range from 4.5V to 38V with excellent load and line
regulations. The switching frequency of SGM6232 is
1.4MHz and current mode operation provides fast
transient response and eases loop stabilization.
The SGM6232 is highly efficient with peak efficiency at
91% when in operation. In shutdown mode the regulator
draws less than 18µA of supply current. Protection
features include cycle-by-cycle current limit and thermal
shutdown. The device also includes an internal soft-start
and an external adjustable soft-start function to limit the
inrush current and prevent the overshoot of output
voltage.
Distributed Power Systems
The SGM6232 is available in Green SOIC-8 (Exposed
Pad) package and requires a minimum number of readily
available external components to complete a 2A step-
down DC/DC converter solution.
Battery Chargers
Flat Panel TVs
Set-Top Boxes
Pre-Regulator for Linear Regulators
Cigarette Lighter Powered Devices
DVD/PVR Devices
FEATURES
●
2A Output Current
●
High Efficiency: Up to 91%
●
4.5V to 38V Input Voltage Range
●
< 18µA Shutdown Supply Current
●
100mΩ Internal Power MOSFET Switch
●
Fixed 1.4MHz Switching Frequency
●
Output Adjustable from 0.8V to 28V
●
Cycle-by-Cycle Current Limit Protection
●
Thermal Shutdown Protection
●
Under-Voltage Lockout
●
Stable with Low ESR Ceramic Capacitors
●
-40℃ to +85℃ Operating Temperature Range
●
Available in Green SOIC-8 (Exposed Pad) Package
APPLICATIONS
TYPICAL APPLICATION
R4
C5
10Ω or shorted 10nF
INPUT
4.5V to 38V
100
IN
BS
SW
L
4.7μH
90
OUTPUT
3.3V/2A
V
OUT
= 5.0V
V
OUT
= 3.3V
ENABLE
EN
SGM6232
SS
GND
C
IN
22μF
C4
0.1μF
Efficiency (%)
C
OUT
47μF
80
70
60
50
40
30
0
0.5
1
1.5
2
FB
COMP
C6
Optional
C3
5.6nF
R3
10kΩ
D1
B340A
R1
33kΩ
R2
10.5kΩ
V
IN
= 12V
2.5
3
3.5
Load Current (A)
SG Micro Corp
www.sg-micro.com
REV. A. 1
SGM6232
2A, 38V, 1.4MHz Step-Down Converter
PACKAGE/ORDERING INFORMATION
MODEL
PIN-
PACKAGE
SOIC-8
(Exposed Pad)
SPECIFIED
TEMPERATURE
RANGE
-40°C to +85°C
ORDERING
NUMBER
SGM6232YPS8G/TR
PACKAGE
MARKING
SGM
6232YPS8
XXXXX
PACKAGE
OPTION
Tape and Reel, 2500
SGM6232
NOTE:
XXXXX
= Date Code and Vendor Code.
ABSOLUTE MAXIMUM RATINGS
Supply Voltage V
IN
................................................... -0.3V to 40V
SW Voltage V
SW
.............................................-0.5V to V
IN
+ 0.3V
Boost Voltage V
BS
................................... V
SW
- 0.3V to V
SW
+ 6V
All Other Pins.............................................................-0.3V to 6V
Package Thermal Resistance
SOIC-8 (Exposed Pad),
θ
JA
.............................................50℃/W
Operating Temperature Range............................-40°C to +85°C
Junction Temperature........................................................150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (Soldering, 10s)...................................260°C
ESD Susceptibility
HBM...................................................................................4000V
MM.......................................................................................200V
CAUTION
This integrated circuit can be damaged by ESD if you don’t pay
attention to ESD protection. SGMICRO recommends that all
integrated circuits be handled with appropriate precautions.
Failure to observe proper handling and installation procedures
can cause damage. ESD damage can range from subtle
performance degradation to complete device failure. Precision
integrated circuits may be more susceptible to damage because
very small parametric changes could cause the device not to
meet its published specifications.
SGMICRO reserves the right to make any change in circuit
design, specification or other related things if necessary without
notice at any time. Please contact SGMICRO sales office to get
the latest datasheet.
NOTE:
Stresses beyond those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device. These
are stress ratings only, and functional operation of the device at
these or any other conditions beyond those indicated in the
operational sections of the specifications is not implied.
Exposure to absolute maximum rating conditions for extended
periods may affect device reliability.
SG Micro Corp
www.sg-micro.com
2
SGM6232
2A, 38V, 1.4MHz Step-Down Converter
PIN CONFIGURATION
(TOP VIEW)
BS
1
8
SS
GND
IN
2
3
7
6
EN
SW
COMP
GND
4
SOIC-8 (Exposed Pad)
5
FB
PIN DESCRIPTION
PIN
1
NAME
BS
FUNCTION
High-side Gate Drive Boost Input. BS supplies the driver for the high-side N-Channel MOSFET
switch. Connect a 10nF or greater capacitor from SW to BS to power the high-side switch. A 10Ω
resistor placed between SW and BS cap is strongly recommended to reduce SW spike voltage.
Power Input. IN supplies the power to the IC, as well as the step-down converter switches. Drive
IN with a 4.5V to 38V power source. Bypass IN to GND with a sufficiently large capacitor to
eliminate noise on the input to the IC.
Power Switching Output. SW is the switching node that supplies power to the output. Connect
the output LC filter from SW to the output load. Note that a capacitor is required from SW to BS
to power the high-side switch.
Ground. (Connect the exposed pad on backside to pin 4.)
Feedback Input. The voltage at this pin is regulated to 0.8V. Connected to the resistor divider
between output and ground to set output voltage.
Compensation Node. COMP is used to compensate the regulation control loop. Connect a
series RC network from COMP to GND to compensate the regulation control loop. In some
cases, an additional capacitor from COMP to GND is required.
Enable Input. EN is a digital input that turns the regulator on or off. Drive EN high to turn on the
regulator, and drive EN low to turn it off. Output voltage is discharged when the IC is off. For
automatic startup, leave EN unconnected.
Soft-Start Control Input. SS controls the soft-start period. Connect a capacitor from SS to GND
to set the soft-start period. A 0.1µF capacitor sets the soft-start period to 10ms. To disable the
soft-start feature, leave SS unconnected.
Power Ground Exposed Pad. Must be connected to GND plane.
2
IN
3
4
5
6
SW
GND
FB
COMP
7
EN
8
Exposed
Pad
SS
GND
SG Micro Corp
www.sg-micro.com
3
SGM6232
(V
IN
= 12V, T
A
= +25°C, unless otherwise noted.)
PARAMETER
Input Voltage Range
Feedback Voltage
Shutdown Supply Current
Quiescent Supply Current
High-side Switch (M1) On-Resistance
Low-side Switch (M2) On-Resistance
Error Amplifier Transconductance
Error Amplifier Voltage Gain
SW Leakage Current
Current Limit
Current Sense to COMP Transconductance
Maximum Duty Cycle
Minimum Duty Cycle
EN Threshold Voltage
EN Threshold Voltage
EN Pull-Up Current
Oscillator Frequency
Short Circuit Oscillator Frequency
Under-Voltage Lockout Threshold
Under-Voltage Lockout
Threshold Hysteresis
Soft-Start Period
Thermal Shutdown Temperature
T
SHDN
f
OSC
SYMBOL
V
IN
V
FB
I
SHDN
I
Q
R
ONH
R
ONL
G
EA
A
EA
I
LSW
I
LIM
G
CS
D
MAX
D
MIN
V
IH
V
IL
2A, 38V, 1.4MHz Step-Down Converter
ELECTRICAL CHARACTERISTICS
CONDITIONS
MIN
4.5
0.776
V
EN
= 0V
V
EN
= 2.6V, V
FB
= 1V
0.8
10
0.8
100
10
∆V
FB
= ±12.5mV
V
EN
= 0V, V
SW
= 0V
4.2
6.2
V
FB
= 0.6V
V
FB
= 1V
1.2
0.4
V
EN
= 0V
V
FB
= 0V
V
IN
Rising
3.5
0.8
1.15
1.4
1.4
140
3.8
230
C
SS
= 0.1μF
10
160
4.2
2
1.6
80
0
500
800
10000
1
1120
TYP
MAX
38
0.824
18
1.7
UNITS
V
V
μA
mA
mΩ
Ω
μA/V
V/V
μA
A
A/V
%
%
V
V
μA
MHz
kHz
V
mV
ms
℃
SG Micro Corp
www.sg-micro.com
4
SGM6232
2A, 38V, 1.4MHz Step-Down Converter
TYPICAL PERFORMANCE CHARACTERISTICS
V
IN
= 12V, C
IN
= 22µF, C
OUT
= 47µF and T
A
= +25°C, unless otherwise noted.
Feedback Voltage vs. Temperature
0.83
Feedback Voltage (V)
0.82
Efficiency vs. Load Current
100
90
80
Efficiency (%)
70
60
50
40
30
V
IN
= 12V
0
0.5
1
1.5
2
2.5
Load Current (A)
3
3.5
V
OUT
= 3.3V
V
OUT
= 5.0V
0.81
0.80
0.79
0.78
0.77
-50
-25
0
25
50
75
100
Temperature (℃)
Efficiency vs. Load Current
100
90
Efficiency (%)
80
70
60
50
40
30
0
0.5
1
1.5
2
2.5
Load Current (A)
3
3.5
V
IN
= 24V
V
OUT
= 2.4V
V
OUT
= 5.0V
Efficiency vs. Load Current
100
90
80
Efficiency (%)
70
60
50
40
30
0
0.5
1
1.5
2
2.5
Load Current (A)
3
3.5
V
IN
= 36V
V
OUT
= 5.0V
SG Micro Corp
www.sg-micro.com
5