MP2303
3A, 28V, 340KHz Synchronous Rectified
Step-Down Converter
The Future of Analog IC Technology
DESCRIPTION
The MP2303 is a monolithic synchronous buck
regulator. The device integrates power
MOSFETS that provide 3A continuous load
current over a wide operating input voltage of
4.75V to 28V. Current mode control provides
fast transient response and cycle-by-cycle
current limit.
An adjustable soft-start prevents inrush current
at turn-on. In shutdown mode, the supply
current drops to 1μA.
This device, available in 8-pin SOIC and 3x3
10-pin QFN packages, provides a very compact
system solution with minimal reliance on
external components.
FEATURES
3A Output Current
Wide 4.75V to 28V Operating Input Range
Integrated Power MOSFET Switches
Output Adjustable from 0.8V to 25V
Up to 95% Efficiency
Programmable Soft-Start
Stable with Low ESR Ceramic Output Capacitors
Fixed 340KHz Frequency
Cycle-by-Cycle Over Current Protection
Input Under Voltage Lockout
Thermally Enhanced 8-Pin SOIC and
3x3 QFN10 Packages
Distributed Power Systems
Pre-Regulator for Linear Regulators
Notebook Computers
APPLICATIONS
EVALUATION BOARD REFERENCE
Board Number
EV2303DN-00A
Dimensions
2.0”X x 1.5”Y x 0.5”Z
All MPS parts are lead-free and adhere to the RoHS directive. For MPS green
status, please visit MPS website under Products, Quality Assurance page.
“MPS” and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
TYPICAL APPLICATION
R4
100kΩ
C5
10nF
BS
SS
EN
COMP
FB
C4
0.1μF
100
Efficiency vs
Load Current
R5
47kΩ
V
IN
= 12V
C1
10μF/35V x 2
MP2303
SW
GND
EFFICIENCY (%)
VIN
IN
90
80
70
60
50
0
0.5
1.0
1.5
2.0
2.5
3.0
V
IN
= 24V
L1
15μH
C2
22μF/10V x 2
R1
52.3kΩ
1%
R2
10kΩ
1%
C6
NS
C3
3.3nF
R3
6.98kΩ
VOUT
5V/3A
V
OUT
= 5V
LOAD CURRENT (A)
MP2303-EC01
MP2303 Rev. 1.0
2/8/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
1
MP2303 – 3A, 28V, 340KHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
ORDERING INFORMATION
Part Number
MP2303DN*
MP2303DQ**
Package
SOIC8E (Exposed Pad)
QFN10 (3mm x 3mm)
Top Marking
MP2303DN
K2
Temperature
–40C to +85C
MP2303DQ
* For Tape & Reel, add suffix –Z (e.g. MP2303DN–Z);
For RoHS compliant packaging, add suffix –LF (e.g. MP2303DN–LF–Z)
** For Tape & Reel, add suffix –Z (e.g. MP2303DQ–Z);
For RoHS compliant packaging, add suffix –LF (e.g. MP2303DQ–LF–Z)
PACKAGE REFERENCE
TOP VIEW
TOP VIEW
IN
BS
IN
SW
GND
1
2
3
4
8
7
6
5
SS
EN
COMP
FB
1
2
3
4
5
10
9
8
7
6
SS
BS
EN
COMP
FB
SW
GND
GND
GND
MP2303_PD01_SOIC8N
EXPOSED PAD
ON BACKSIDE
MP2303_PD02_QFN10
SOIC8E (Exposed Pad)
QFN10 (3mm x 3mm)
ABSOLUTE MAXIMUM RATINGS
(1)
Supply Voltage V
IN
.......................–0.3V to +30V
Switch Voltage V
SW
...................................... 31V
Boost Voltage V
BS
..........V
SW
– 0.3V to V
SW
+ 6V
All Other Pins .................................–0.3V to +6V
Junction Temperature ...............................150°C
Continuous Power Dissipation
(T
A
= +25°C)
(2)
SOIC8E...................................................... 2.5W
QFN10 (3mmx3mm) .................................. 2.5W
Lead Temperature ....................................260°C
Storage Temperature ............. –65°C to +150°C
Recommended Operating Conditions
(3)
Input Voltage V
IN
............................ 4.75V to 28V
Output Voltage V
OUT
........................ 0.8V to 25V
Ambient Operating Temperature ... –40°C to +85°C
Thermal Resistance
(4)
SOIC8E .................................. 50 ...... 10...
C/W
3x3 QFN10 ............................. 50 ...... 12...
C/W
Notes:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature T
J
(MAX), the junction-to-
ambient thermal resistance
θ
JA
, and the ambient temperature
T
A
. The maximum allowable continuous power dissipation at
any
ambient
temperature
is
calculated
by
P
D
(MAX)=(T
J
(MAX)-T
A
)/
θ
JA
. Exceeding the maximum
allowable power dissipation will cause excessive die
temperature, and the regulator will go into thermal shutdown.
Internal thermal shutdown circuitry protects the device from
permanent damage.
3) The device is not guaranteed to function outside of its
operating conditions.
4) Measured on JESD51-7 4-layer board.
θ
JA
θ
JC
MP2303 Rev. 1.0
2/8/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
2
MP2303 – 3A, 28V, 340KHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
ELECTRICAL CHARACTERISTICS
(5)
V
IN
= 12V, T
A
= +25°C, unless otherwise noted.
Parameter
Shutdown Supply Current
Supply Current
Feedback Voltage
OVP Threshold Voltage
Error Amplifier Voltage Gain
Error Amplifier Transconductance
High-Side Switch-On Resistance
Low-Side Switch-On Resistance
High-Side Switch Leakage Current
Upper-Switch Current Limit
Lower-Switch Current Limit
COMP to Current Sense
Transconductance
Oscillation Frequency
Short Circuit Oscillation Frequency
Maximum Duty Cycle
Minimum On-Time
EN Shutdown Threshold Voltage
EN Shutdown Threshold Voltage
Hysteresis
EN Lockout Threshold Voltage
EN Lockout Hysteresis
Input Under Voltage Lockout
Threshold
Input Under Voltage Lockout
Threshold Hysterisis
Soft-Start Current
Thermal Shutdown
UVLO
V
IN
rising, T
A
= +25
°
C
–40
°
C
≤
T
A
≤
+85
°
C
3.8
3.5
210
V
SS
= 0V
6
160
V
FB
Symbol Condition
V
EN
= 0V
V
EN
= 2.7V, V
FB
= 1.0V
4.75V
V
IN
28V,
T
A
= +25
°
C
–40
°
C
≤
T
A
≤
+85
°
C
A
EA
G
EA
R
DS(ON)1
R
DS(ON)2
V
EN
= 0V, V
SW
= 0V
4.3
From Drain to Source
G
CS
F
osc1
F
osc2
D
MAX
T
A
= +25
°
C
–40
°
C
≤
T
A
≤
+85
°
C
V
FB
= 0V
V
FB
= 0.7V
V
EN
Rising
1.1
300
270
110
90
220
1.5
220
2.2
–40
°
C
≤
T
A
≤
+85
°
C
2.1
210
4.05
4.30
4.70
2.5
2.7
2.8
I
C
=
10μA
550
0.780
0.772
0.90
0.95
400
820
125
125
0
6.3
1.25
9
340
380
400
Min
Typ
(5)
0.3
1.3
0.800
Max
3.0
1.5
0.820
0.828
1.00
1100
Units
μA
mA
V
V
V
V/V
μA/V
mΩ
mΩ
μA
A
A
A/V
KHz
KHz
KHz
%
ns
V
mV
V
V
mV
V
V
mV
μA
°C
10
8.3
(5)
2.0
Note:
5) 100% production test at +25°C. Specifications over the temperature range are guaranteed by design and characterization.
6) Guaranteed by design
MP2303 Rev. 1.0
2/8/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
3
MP2303 – 3A, 28V, 340KHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
PIN FUNCTIONS
3x3
SOIC8N
QFN10
Pin #
Pin #
1
9
Name Description
High-Side Gate Drive Boost Input. BS supplies the drive for the high-side N-
BS
Channel MOSFET switch. Connect a 0.01μF or greater capacitor from SW to BS
to power the high side switch.
Power Input. IN supplies the power to the IC, as well as the step-down converter
switches. Drive IN with a 4.75V to 28V power source. Bypass IN to GND with a
IN
suitably large capacitor to eliminate noise on the input to the IC. See
Input
Capacitor.
Power Switching Output. SW is the switching node that supplies power to the
SW
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. SOIC8: Connect the exposed pad to pin 4. 3x3 QFN10: Connect to pins
GND
3, 4 and 5 and ensure that said pins are tied together.
Feedback Input. FB senses the output voltage to regulate that voltage. Drive FB
FB
with a resistive voltage divider from the output voltage. The feedback reference
voltage is 0.8V. See
Setting the 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
COMP
control loop. In some cases, an additional capacitor from COMP to GND is
required. See
Compensation Components.
Enable Input. EN is a digital input that turns the regulator on or off. Drive EN higher
than 2.7V to turn on the regulator, drive it lower than 1.1V to turn it off. Pull up by a
EN
resistive voltage divider to the IN pin for automatic startup, a 47kΩ resistor from
EN to Ground and a 100kΩ resistor from EN to V
IN
.
Soft-start Control Input. SS controls the soft-start period. Connect a capacitor from
SS
SS to GND to set the soft-start period. See
Soft-Start Capacitor.
2
1
3
4
5
2
3, 4, 5
6
6
7
7
8
8
10
MP2303 Rev. 1.0
2/8/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
4
MP2303 – 3A, 28V, 340KHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS
V
IN
= 12V, V
O
= 3.3V, L = 10µH, C1 = 10µF, C2 = 22µF x 2, T
A
= +25°C, unless otherwise noted.
Feeback Voltage vs.
Efficiency vs
Temperature
Load Current
95
0.810
FEEDBACK VOLTAGE (V)
90
V
IN
= 12V
EFFICIENCY (%)
85
80
75
70
65
60
55
50
0
0.5
1.0
1.5
2.0
0.805
0.800
0.795
0.790
0.7850
0.780
-40
V
IN
= 12V
V
IN
= 28V
V
IN
= 24V
V
IN
= 4.75V
V
OUT
= 2.5V
2.5
3.0
3.5
-20
LOAD CURRENT (A)
MP2303-EC02
TEMPERATURE (oC)
0
20
40
60
80
MP2303-TPC01
UVLO Rising vs.
Temperature
4.5
2.70
Enable Lockout Threshold
vs. Temperature
345
2.65
2.60
2.55
2.50
2.45
2.40
2.35
Oscillator Frequency
UVLO THRESHOLD (V)
4.4
4.3
4.2
4.1
4.0
3.9
3.8
3.7
-40
-20
0
20
40
60
80
ENABLE VOLTAGE (V)
FREQUENCY (KHz)
340
335
330
TEMPERATURE (oC)
2.30
-40
-20
TEMPERATURE (oC)
0
20
40
60
80
325
-40
-20
TEMPERATURE (oC)
0
20
40
60
80
MP2303-TPC02
MP2303-TPC03
MP2303-TPC04
MP2303 Rev. 1.0
2/8/2013
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
5
