MP2301E. Przecież pisałem, że jest w serwisówce! Pin w pin - MP2363, MP1482DN, MP1484, MP1580 i trochę innych. I tak pewnie trzeba każdy "przeliczyć" i zmienić rezystory, żeby uzyskać 3,3V.
MP2303A
3A, 28V, 360kHz Synchronous Rectified
Step-Down Converter
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP2303A is a monolithic synchronous
buck regulator. The device integrates a 150mΩ
high-side MOSFET and a 80mΩ low-side
MOSFET that provide 3A continuous load
current over a wide operating input voltage of
4.7V 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 lower than 1μA.
This device, available in an 8-pin SOIC and
PDIP-8 packages, provides a very compact
system solution with minimal reliance on
external components.
3A Output Current
Wide 4.7V to 28V Operating Input Range
Integrated MOSFET Switches
Output Adjustable from 0.80V to 25V
Up to 95% Efficiency
Programmable Soft-Start
Stable with Low ESR Ceramic Output Capacitors
Fixed 360kHz Frequency
Cycle-by-Cycle Over Current Protection
Input Under Voltage Lockout
Available in thermally enhanced 8-Pin SOIC
and PDIP-8 packages
APPLICATIONS
Distributed Power Systems
Pre-Regulator for Linear Regulators
Notebook Computers
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
C5
10nF
100
VIN=5V
90
7
8
2
IN
EN
1
BS
3
SW
80
5
70
MP2303A
SS
GND
4
VIN=12V
FB
COMP
6
VIN=28V
VIN=24V
60
50
40
MP2303A Rev.1.1
7/25/2012
VOUT=3.3
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5
OUTPUT CURRENT
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1
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
ORDERING INFORMATION
Part Number
MP2303ADN*
MP2303ADP**
Package
SOIC8E
PDIP8
Top Marking
M2303ADN
MP2303A
Free Air Temperature (TA)
-40C to +85C
-40C to +85C
* For Tape & Reel, add suffix –Z (e.g. MP2303ADN–Z);
For RoHS compliant packaging, add suffix –LF (e.g. MP2303ADN–LF–Z)
** For Tape & Reel, add suffix –Z (e.g. MP2303ADP–Z);
For RoHS compliant packaging, add suffix –LF (e.g. MP2303ADP–LF–Z)
PACKAGE REFERENCE
TOP VIEW
TOP VIEW
BS
1
8
IN
2
7
3
6
GND
4
5
SS
2
7
EN
3
6
COMP
GND
FB
8
SW
COMP
1
IN
EN
SW
BS
SS
4
5
FB
MP2303A_PD01-PDIP8
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance
Supply Voltage VIN ........................-0.3V to +30V
Switch Voltage VSW .................. -1V to VIN + 0.3V
Boost Voltage VBS .......... VSW - 0.3V to VSW + 6V
All Other Pins ..................................-0.3V to +6V
Junction Temperature ...............................150°C
Continuous Power Dissipation
(TA =
+25°C)(2)
SOIC8E ...................................................... 2.5W
PDIP8 ........................................................ 1.2W
Lead Temperature ....................................260°C
Storage Temperature .............. -65°C to +150°C
SOIC8E .................................. 50 ...... 10... C/W
PDIP8 .................................... 105 ..... 45... C/W
Recommended Operating Conditions
(3)
Input Voltage VIN .............................. 4.7V to 28V
Output Voltage VOUT ....................... 0.80V to 25V
Maximum Junction Temp. (TJ) ................ +125°C
MP2303A Rev.1.1
7/25/2012
(4)
θJA
θJC
Notes:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ (MAX), the junction-toambient thermal resistance θJA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD (MAX) = (TJ
(MAX)-TA)/θJA. 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 PCB..
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2
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
ELECTRICAL CHARACTERISTICS (5)
VIN = 12V, TA = +25°C, unless otherwise noted.
Parameter
Symbol Condition
Shutdown Supply Current
Supply Current
VEN = 0V
VEN = 2.7V, VFB = 1.0V
Feedback Voltage
4.7V VIN 28V,
TA = +25°C
0.780
-40°C ≤ TA ≤ +85°C
Typ (5)
Max
Units
0.3
1.45
Min
3.0
1.6
μA
mA
0.800
0.820
V
0.835
V
0.765
OVP Threshold Voltage
Error Amplifier Voltage Gain
VFB
0.90
0.95
400
1.00
V
V/V
550
820
1100
μA/V
10
mΩ
mΩ
μA
A
A
AEA
Error Amplifier Transconductance
GEA
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
IC = 10μA
RDS(ON)1
RDS(ON)2
VEN = 0V, VSW = 0V
4.3
From Drain to Source
Short Circuit Oscillation Frequency
Maximum Duty Cycle
Minimum On Time
EN Shutdown Threshold Voltage
EN Threshold Voltage Hysteresis
EN Input Current
Fosc2
DMAX
Input Under Voltage Lockout
Threshold Hysterisis
Soft-Start Current
Thermal Shutdown
TA = +25°C
310
-40°C ≤ TA ≤ +85°C
290
VFB = 0V
VFB = 0.7V
85
VEN Rising
Fosc1
Input Under Voltage Lockout
Threshold
7
GCS
Oscillation Frequency
150
80
0
6.0
1.25
1.0
360
55
90
180
1.3
205
410
kHz
430
kHz
2
VIN rising, TA = +25°C
3.6
0°C ≤ TA ≤ +70°C
3.2
3.95
kHz
%
ns
V
mV
μA
4.3
V
4.5
VEN = 5V
UVLO
A/V
V
1.6
125
VSS = 0V
mV
6
160
μA
°C
Notes:
5) 100% production test at +25°C. Specifications over the temperature range are guaranteed by design and characterization.
MP2303A Rev.1.1
7/25/2012
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3
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
PIN FUNCTIONS
Pin #
1
2
3
4
5
6
7
8
Name Description
High-Side Gate Drive Boost Input. BS supplies the drive for the high-side N-Channel MOSFET
BS
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.
IN
Drive IN with a 4.7V to 28V power source. Bypass IN to GND with a 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 output. Connect
SW
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.
GND Ground (Connect Exposed Pad to Pin 4)
Feedback Input. FB senses the output voltage to regulate that voltage. Drive FB with a
FB
resistive voltage divider from the output voltage. The feedback threshold is 0.80V. 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 control loop. In some
COMP
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 high to turn on
EN
the regulator, drive it low to turn it off. Connect EN with IN through a resistive voltage divider
for automatic startup. Do not float this pin.
Soft-start Control Input. SS controls the soft-start period. Connect a capacitor from SS to GND
SS
to set the soft-start period. A 0.1μF capacitor sets the soft-start period to 15ms. To disable the
soft-start feature, leave SS unconnected.
MP2303A Rev.1.1
7/25/2012
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4
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 12V, VOUT = 3.3V, TA = +27ºC, unless otherwise noted.
1.6
120
100
5
80
4
60
3
40
1.4
6
2
1.2
1.0
0.8
0.6
0.4
20
0.2
0
VFB=1V
0
5
10
15
4.0
20
25
30
0
10
20
30
40
50
1.0
VIN=28V
3.5
0
1
VEN=0V
0
0.2
0.4
0.6
-0.5
VIN=5V
1.5
VIN=24V
1.0
0.5
0
-0.5
-1.5
VIN=12V
1
MP2303A Rev.1.1
7/25/2012
2
3
4
5
6
-3.0
0
0.5
1
IOUT=3A
-1.0
VIN=5V
VIN=12V
VIN=24V
VIN=28V
-2.0
-2.5
0
1.0
IOUT=1.5A
0
-1.0
2.0
0.8
0.5
0
2.5
VFB=0.6V
1.0
0.5
3.0
0
-1.5
1.5 2.0 2.5 3.0 3.5
-2.0
0
5
10
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15
20
25
30
5
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 12V, VOUT = 3.3V, TA = +27ºC, unless otherwise noted.
VOUT
200mV/div
VOUT
2V/div
VEN
2V/div
IINDUCTOR
2A/div
VOUT
2V/div
VEN
2V/div
VSW
10V/div
VSW
10V/div
IINDUCTOR
2A/div
VOUT
2V/div
VSW
20V/div
VOUT
2V/div
VEN
2V/div
VEN
2V/div
IINDUCTOR
2A/div
VOUT
2V/div
VSW
10V/div
IINDUCTOR
2A/div
VIN
5V/div
VSW
5V/div
IINDUCTOR
2A/div
VSW
20V/div
IINDUCTOR
2A/div
4ms/div
VOUT
2V/div
VIN
5V/div
VSW
5V/div
IINDUCTOR
2A/div
4ms/div
MP2303A Rev.1.1
7/25/2012
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6
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 12V, VOUT = 3.3V, TA = +27ºC, unless otherwise noted.
MP2303A Rev.1.1
7/25/2012
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© 2012 MPS. All Rights Reserved.
7
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
BLOCK DIAGRAM
+
CURRENT
SENSE
AMPLIFIER
OVP
0.95V
-OSCILLATOR
+
FB
360kHz
0.3V
RAMP
5V
BS
--
--
+
+
ERROR
AMPLIFIER
S
Q
R
--
0.8V
+
--
CLK
+
SS
IN
Q
SW
CURRENT
COMPARATOR
COMP
GND
EN
1.2V
OVP
IN & lt; 3.95V
IN
-INTERNAL
REGULATORS
1.3 V
+
SHUTDOWN
COMPARATOR
Figure 1—Functional Block Diagram
OPERATION
FUNCTIONAL DESCRIPTION
The MP2303A is a synchronous rectified,
current-mode, step-down regulator. It regulates
input voltages from 4.7V to 28V down to an
output voltage as low as 0.80V, and supplies up
to 3A of load current.
The MP2303A uses current-mode control to
regulate the output voltage. The output voltage
is measured at FB through a resistive voltage
divider and amplified through the internal
transconductance error amplifier. The voltage at
COMP pin is compared to the switch current
measured internally to control the output
voltage.
MP2303A Rev.1.1
7/25/2012
The converter uses internal N-Channel
MOSFET switches to step-down the input
voltage to the regulated output voltage. Since
the high side MOSFET requires a gate voltage
greater than the input voltage, a boost capacitor
connected between SW and BS is needed to
drive the high side gate. The boost capacitor is
charged from the internal 5V rail when SW is low.
When the MP2303A FB pin exceeds 20% of the
nominal regulation voltage of 0.80V, the over
voltage comparator is tripped and latched; the
COMP pin and the SS pin are discharged to
GND, forcing the high-side switch off.
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8
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
APPLICATIONS INFORMATION
COMPONENT SELECTION
Setting the Output Voltage
The output voltage is set using a resistive
voltage divider from the output voltage to FB pin.
The voltage divider divides the output voltage
down to the feedback voltage by the ratio:
VFB VOUT
R2
R1 R2
Thus the output voltage is:
VOUT 0.80
inductor will result in less ripple current that will
result in lower output ripple voltage. However,
the larger value inductor will have a larger
physical size, higher series resistance, and/or
lower saturation current. A good rule for
determining the inductance to use is to allow
the peak-to-peak ripple current in the inductor
to be approximately 30% of the maximum
switch current limit. Also, make sure that the
peak inductor current is below the maximum
switch current limit. The inductance value can
be calculated by:
R1 R2
R2
Where VFB is the feedback voltage and VOUT is
the output voltage.
A typical value for R2 can be as high as 100kΩ,
but a typical value is 10kΩ. Using that value, R1
is determined by:
R1 12.5 ( VOUT 0.80)(k)
For example, for a 3.3V output voltage, R2 is
10kΩ, and R1 is 31.25kΩ.
L
VOUT
V
1 OUT
fS ΔI
VIN
Where VIN is the input voltage, fS is the
switching frequency, and ΔIL is the peak-topeak inductor ripple current.
Choose an inductor that will not saturate under
the maximum inductor peak current. The peak
inductor current can be calculated by:
ILP ILOAD
VOUT
V
1 OUT
2 fS L
VIN
Configuring the EN control
Where ILOAD is the load current.
EN high to turn on the regulator and EN low to
turn it off. Do not float the pin.
Optional Schottky Diode
For automatic start-up the EN pin can be pulled
up to input voltage through a resistive voltage
divider. Choose the values of the pull-up
resistor (RUP from VIN to EN pin) and pull-down
resistor (RDOWN from EN pin to GND) to
determine the automatic start-up voltage:
VINSTART 1.3
(RUP RDOWN )
(V)
RDOWN
For example, for RUP=100kΩ and RDOWN=20kΩ,
the VIN-START is set at 7.8V.
Note the EN voltage should be no greater than
6V. If the resistive voltage divider will make it
run over, please use a zener (below 6V) to
clamp it.
During the transition between high-side switch
and low-side switch, the body diode of the lowside power MOSFET conducts the inductor
current. The forward voltage of this body diode
is high. An optional Schottky diode may be
paralleled between the SW pin and GND pin to
improve overall efficiency. Table 2 lists example
Schottky diodes and their Manufacturers.
Table 2—Diode Selection Guide
B340
SK34
Voltage/Current
Rating
40V, 3A
40V, 3A
MBRS340
40V, 3A
Part Number
Vendor
Diodes, Inc.
Diodes, Inc.
International
Rectifier
To avoid noise, a 10nF ceramic capacitor from
EN to GND is recommended.
Inductor
The inductor is required to supply constant
current to the output load while being driven by
the switched input voltage. A larger value
MP2303A Rev.1.1
7/25/2012
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9
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
Input Capacitor
The input current to the step-down converter is
discontinuous, therefore a capacitor is required to
supply the AC current to the step-down converter
while maintaining the DC input voltage. Use low
ESR capacitors for the best performance.
Ceramic capacitors are preferred, but tantalum or
low-ESR electrolytic capacitors may also suffice.
Choose X5R or X7R dielectrics when using
ceramic capacitors.
Since the input capacitor (C1) absorbs the input
switching current it requires an adequate ripple
current rating. The RMS current in the input
capacitor can be estimated by:
IC1 ILOAD
V
VOUT
(1 OUT )
VIN
VIN
ILOAD
2
For simplification, choose the input capacitor
whose RMS current rating greater than half of
the maximum load current.
The input capacitor can be electrolytic, tantalum
or ceramic. When using electrolytic or tantalum
capacitors, a small, high quality ceramic
capacitor, i.e. 0.1μF, should be placed as close to
the IC as possible. When using ceramic
capacitors, make sure that they have enough
capacitance to provide sufficient charge to
prevent excessive voltage ripple at input. The
input voltage ripple caused by capacitance can be
estimated by:
VIN
ILOAD
V
V
OUT 1 OUT
f S C1 VIN
VIN
Output Capacitor
The output capacitor is required to maintain the
DC output voltage. Ceramic, tantalum, or low
ESR electrolytic capacitors are recommended.
Low ESR capacitors are preferred to keep the
output voltage ripple low. The output voltage
ripple can be estimated by:
VOUT
VOUT
V
1 OUT
fS L
VIN
MP2303A Rev.1.1
7/25/2012
In the case of ceramic capacitors, the impedance
at the switching frequency is dominated by the
capacitance. The output voltage ripple is mainly
caused by the capacitance. For simplification, the
output voltage ripple can be estimated by:
ΔVOUT
1
R ESR
8 f S C2
V
1 OUT
VIN
L C2
VOUT
8 fS
2
In the case of tantalum or electrolytic capacitors,
the ESR dominates the impedance at the
switching frequency. For simplification, the output
ripple can be approximated to:
ΔVOUT
The worst-case condition occurs at VIN = 2VOUT,
where:
I C1
Where C2 is the output capacitance value and
RESR is the equivalent series resistance (ESR)
value of the output capacitor.
V
VOUT
1 OUT
fS L
VIN
R ESR
The characteristics of the output capacitor also
affect the stability of the regulation system. The
MP2303A can be optimized for a wide range of
capacitance and ESR values.
Compensation Components
MP2303A employs current mode control for
easy compensation and fast transient response.
The system stability and transient response are
controlled through the COMP pin. COMP pin is
the output of the internal transconductance
error amplifier. A series capacitor-resistor
combination sets a pole-zero combination to
control the characteristics of the control system.
The DC gain of the voltage feedback loop is
given by:
A VDC R LOAD G CS A VEA
VFB
VOUT
Where AVEA is the error amplifier voltage gain,
GCS is the current sense transconductance,
RLOAD is the load resistor value.The system has
2 poles of importance. One is due to the
compensation capacitor (C3) and the output
resistor of error amplifier, and the other is due
to the output capacitor and the load resistor.
These poles are located at:
fP1
GEA
2 C3 A VEA
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10
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
fP2
Table 3—Compensation Values for Typical
Output Voltage/Capacitor Combinations
1
2 C2 R LOAD
is
the
error
amplifier
Where
GEA
transconductance, and RLOAD is the load resistor
value.
The system has one zero of importance, due to the
compensation
capacitor
(C3)
and
the
compensation resistor (R3). This zero is located at:
f Z1
1
2 C3 R3
1
2 C2 R ESR
In this case, a third pole set by
compensation capacitor (C6) and
compensation resistor (R3) is used
compensate the effect of the ESR zero on
loop gain. This pole is located at:
fP 3
1.8V
4.7μH
2.5V
3.3V
12V
2.5V
3.3V
5V
the
the
to
the
1
2 C6 R3
The goal of compensation design is to shape
the converter transfer function to get a desired
loop gain. The system crossover frequency
where the feedback loop has the unity gain is
important.
Lower crossover frequencies result in slower
line and load transient responses, while higher
crossover frequencies could cause system
unstable. A good rule of thumb is to set the
crossover frequency to approximately one-tenth
of the switching frequency. Switching frequency
for the MP2303A is 360kHz, so the desired
crossover frequency is 36kHz.
Table 3 lists the typical values of compensation
components for some standard output voltages
with various output capacitors and inductors. The
values of the compensation components have
been optimized for fast transient responses and
good stability at given conditions.
MP2303A Rev.1.1
7/25/2012
L1
5V
The system may have another zero of
importance, if the output capacitor has a large
capacitance and/or a high ESR value. The zero,
due to the ESR and capacitance of the output
capacitor, is located at:
fESR
VOUT
12V
4.76.8μH
6.810μH
1015μH
1522μH
4.76.8μH
6.810μH
1015μH
1522μH
C2
100μF
Ceramic
47μF
Ceramic
22μFx2
Ceramic
22μFx2
Ceramic
22μFx2
Ceramic
560μF Al.
30mΩ ESR
560μF Al
30mΩ ESR
470μF Al.
30mΩ ESR
220μF Al.
30mΩ ESR
R3
C3
C6
8.2kΩ 3.3nF None
5.6kΩ 4.7nF None
7.5kΩ 4.7nF None
10kΩ 3.3nF None
25kΩ 3.3nF None
70kΩ 3.3nF 150pF
90kΩ 3.3nF 100pF
100kΩ 3.3nF 50pF
120kΩ 3.3nF 50pF
To optimize the compensation components for
conditions not listed in Table 3, the following
procedure can be used.
1. Choose the compensation resistor (R3) to set
the desired crossover frequency. Determine the
R3 value by the following equation:
R3
2 C2 f C VOUT
G EA G CS
VFB
Where fC is the desired crossover frequency.
2. Choose the compensation capacitor (C3) to
achieve the desired phase margin. For
applications with typical inductor values, setting
the compensation zero, fZ1, below one forth of
the crossover frequency provides sufficient
phase margin. Determine the C3 value by the
following equation:
C3
4
2 R3 f C
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11
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
3. Determine if the second compensation
capacitor (C6) is required. It is required if the
ESR zero of the output capacitor is located at
less than half of the switching frequency, or the
following relationship is valid:
External Bootstrap Diode
An external bootstrap diode may enhance the
efficiency of the regulator, and it will be a must
if the applicable condition is:
VOUT is 5V or 3.3V, and duty cycle is high:
f
1
S
2 C2 R ESR
2
D=
If this is the case, then add the second
compensation capacitor (C6) to set the pole fP3
at the location of the ESR zero. Determine the
C6 value by the equation:
VOUT
& gt; 65%
VIN
In these cases, an external BST diode is
recommended from the output of the voltage
regulator to BST pin, as shown in Figure.2
External BST Diode
IN4148
C2 R ESR
C6
R3
BST
MP2303A
SW
CBST
L
+
COUT
5V or 3.3V
Figure 2—Add Optional External Bootstrap
Diode to Enhance Efficiency
The recommended external BST diode is
IN4148, and the BST cap is 0.1~1µF.
TYPICAL APPLICATION CIRCUITS
C5
10nF
INPUT
4.7V to 28V
7
2
IN
EN
1
BS
3
SW
OUTPUT
2.5V
3A
MP2303A
8 SS
GND
FB
COMP
4
5
6
C6
(optional)
C3
4.7nF
D1
B340
(optional)
Figure 3—MP2303A with AVX 47μF, 6.3V Ceramic Output Capacitor
MP2303A Rev.1.1
7/25/2012
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MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
PCB LAYOUT GUIDE
2)
PCB layout is very important to achieve stable
operation. It is highly recommended to duplicate
EVB layout for optimum performance.
Bypass ceramic capacitors are suggested to
be put close to the VIN Pin.
3)
Ensure all feedback connections are short
and direct. Place the feedback resistors and
compensation components as close to the
chip as possible.
4)
Rout SW away from sensitive analog areas
such as FB.
5)
Connect IN, SW, and especially GND
respectively to a large copper area to cool
the chip to improve thermal performance and
long-term reliability.
If change is necessary, please follow these
guidelines and take Figure 4 for reference.
1)
Keep the path of switching current short and
minimize the loop area formed by Input cap,
high-side MOSFET and low-side MOSFET.
C5
INPUT
4.75V to 23V
2
7
8
C1
1
IN
BS
SW
EN
MP2303A
SS
GND
4
FB
COMP
OUTPUT
R1
5
6
C3
C4
L1
3
D1
(optional)
R2
C2
R3
MP2303A Typical Application Circuit
R3
FB 5
EN 7
COMP 6
3 SW
C3
2 IN
C4
SS 8
R4
PGND
R1
R2
SGND
R1
C5
4 GND
1 BS
PGND
D1
C2
C1
L1
TOP Layer
Bottom Layer
Figure 4―MP2303A Typical Application Circuit and PCB Layout Guide
MP2303A Rev.1.1
7/25/2012
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© 2012 MPS. All Rights Reserved.
13
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
PACKAGE INFORMATION
SOIC8E
0.189(4.80)
0.197(5.00)
8
0.124(3.15)
0.136(3.45)
5
0.150(3.80)
0.157(4.00)
PIN 1 ID
1
0.228(5.80)
0.244(6.20)
0.089(2.26)
0.101(2.56)
4
TOP VIEW
BOTTOM VIEW
SEE DETAIL " A "
0.013(0.33)
0.020(0.51)
0.051(1.30)
0.067(1.70)
SEATING PLANE
0.000(0.00)
0.006(0.15)
0.0075(0.19)
0.0098(0.25)
SIDE VIEW
0.050(1.27)
BSC
FRONT VIEW
0.010(0.25)
x 45o
0.020(0.50)
GAUGE PLANE
0.010(0.25) BSC
0.050(1.27)
0.024(0.61)
0o-8o
0.016(0.41)
0.050(1.27)
0.063(1.60)
DETAIL " A "
0.103(2.62)
0.138(3.51)
RECOMMENDED LAND PATTERN
MP2303A Rev.1.1
7/25/2012
0.213(5.40)
NOTE:
1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN
BRACKET IS IN MILLIMETERS.
2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH,
PROTRUSIONS OR GATE BURRS.
3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH
OR PROTRUSIONS.
4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING)
SHALL BE 0.004 " INCHES MAX.
5) DRAWING CONFORMS TO JEDEC MS-012, VARIATION BA.
6) DRAWING IS NOT TO SCALE.
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© 2012 MPS. All Rights Reserved.
14
MP2303A – 3A, 28V, 360kHz SYNCHRONOUS RECTIFIED, STEP-DOWN CONVERTER
PACKAGE INFORMATION
PDIP8
,
0.367(9.32)
0.387(9.83)
8
5
0.240(6.10)
0.260(6.60)
PIN 1 ID
4
1
TOP VIEW
0.320( 8.13)
0.400(10.16)
0.300(7.62)
0.325(8.26)
0.100(2.54)
BSC
0.125(3.18)
0.145(3.68)
0.015(0.38)
0.035(0.89)
0.120(3.05)
0.140(3.56)
0.050(1.27)
0.065(1.65)
0.015(0.38)
0.021(0.53)
FRONT VIEW
0.008(0.20)
0.014(0.36)
SIDE VIEW
NOTE:
1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN BRACKET IS IN MILLIMETERS.
2) PACKAGE LENGTH AND WIDTH DO NOT INCLUDE MOLD FLASH, OR PROTRUSIONS.
3) DRAWING CONFORMS TO JEDEC MS-001, VARIATION BA.
4) DRAWING IS NOT TO SCALE.
NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications.
Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS
products into any application. MPS will not assume any legal responsibility for any said applications.
MP2303A Rev. 1.1
www.MonolithicPower.com
7/25/2012
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2012 MPS. All Rights Reserved.
15