MP9403
3A, 4.3V to7V Input, 250kHz Integrated
Synchronous Step-Down Converter
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP9403 is a monolithic synchronous buck
regulator. The device integrates a 150mΩ
high-side MOSFET and a 100mΩ low-side
MOSFET that provides 3A continuous load
current over input voltage of 4.3V to 7V. Current
mode control provides fast transient response
and cycle-by-cycle current limit.
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•
•
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An adjustable soft-start prevents inrush current
at turn-on. In shutdown mode, the supply
current drops to 1μA.
This device, available in an 8-pin SOIC
package with exposed pad, provides a very
compact system solution with minimal reliance
on external components.
3A Output Current
4.3V to 7V Operating Input Range
Integrated MOSFET Switches
Output Adjustable from 0.80V to 5.50V
Up to 93% Efficiency
Programmable Soft-Start
Stable with Low ESR Ceramic Output Capacitors
Fixed 250kHz Frequency
Cycle-by-Cycle Over Current Protection
Input Under Voltage Lockout
Thermally Enhanced 8-Pin SOIC Package
APPLICATIONS
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Distributed Power Systems
Pre-Regulator for Linear Regulators
Notebook Computers
“MPS” and “The Future of Analog IC Technology” are Registered Trademarks of
Monolithic Power Systems, Inc.
TYPICAL APPLICATION
Efficiency vs. Load Current
VOUT=2.5V
100
INPUT
4.3V to 7V
90
V IN=4.3V
8
1
BS
3
SW
MP9403
SS
GND
FB
COMP
4
6
C6
(optional)
OUTPUT
2.5V
3A
5
D1
B320
(optional)
EFFICIENCY (%)
80
2
IN
7
EN
70
60
V IN=5V
50
40
V IN=7V
30
20
10
0
0.01
0.1
1
10
LOAD CURRENT (A)
MP9403 Rev.0.9
4/12/2016
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1
MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
ORDERING INFORMATION
Part Number*
MP9403EN
Package
SOIC8E
Top Marking
Free Air Temperature (TA)
MP9403EN
–20° to +85°C
* For Tape & Reel, add suffix –Z (e.g. MP9403EN–Z);
For RoHS Compliant Packaging, add suffix –LF (e.g. MP9403 EN –LF–Z)
PACKAGE REFERENCE
TOP VIEW
BS
1
8
SS
IN
2
7
EN
SW
3
6
COMP
GND
4
5
FB
CONNECT EXPOSED PAD
AND GND PIN TO A CERTAIN
GROUND PLANE
ABSOLUTE MAXIMUM RATINGS (1)
Recommended Operating Conditions
Supply Voltage VIN .........................–0.3V to +8V
Switch Voltage VSW ................. –1V to VIN + 0.3V
Boost Voltage VBS ..........VSW – 0.3V to VSW + 6V
All Other Pins .................................–0.3V to +6V
(2)
Continuous Power Dissipation (TA = +25°C)
............................................................. 2.5W
Junction Temperature ...............................150°C
Lead Temperature ....................................260°C
Storage Temperature ............. –65°C to +150°C
Supply Voltage VIN ............................. 4.3V to 7V
Output Voltage VOUT ....................... 0.8V to 5.5V
Operating Junct. Temp. (TJ)......... –20°C to +125°C
MP9403 Rev.0.9
4/12/2016
Thermal Resistance
(4)
θJA
(3)
θJC
SOIC8E .................................. 50 ...... 10... °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 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 board.
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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
ELECTRICAL CHARACTERISTICS (5)
VIN = 5V, TA = +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 Threshold Voltage Hysteresis
Input Under Voltage Lockout
Threshold
Input Under Voltage Lockout
Threshold Hysterisis
Soft-Start Current
Thermal Shutdown
Symbol Condition
VEN = 0V
VEN = 2.7V, VFB = 1.0V
4.3V ≤ VIN ≤ 7V,
VFB
TA = +25°C
AEA
GEA
ΔIC = ±10μA
Min
1.45
Max
1.0
1.6
Units
μA
mA
0.780
0.800
0.820
V
0.90
0.95
400
820
150
100
1.00
4.3
1.25
V
V/V
μA/V
mΩ
mΩ
μA
A
A
7
A/V
550
RDS(ON)1
RDS(ON)2
VEN = 0V, VSW = 0V
Duty Cycle = 60%
From Drain to Source
UVLO
3.4
TA = +25°C
VFB = 0V
VFB = 0.7V
215
VEN Rising
1.0
VIN rising, TA = +25°C
3.3
VSS = 0V
1100
1.0
GCS
Fosc1
Fosc2
DMAX
Typ (5)
85
250
55
90
180
1.3
205
285
3.65
4.0
1.6
kHz
kHz
%
ns
V
mV
V
45
mV
6
160
μA
°C
Notes:
5) 100% production test at +25°C. Specifications over the temperature range are guaranteed by design and characterization.
MP9403 Rev.0.9
4/12/2016
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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
PIN FUNCTIONS
Pin #
Name
1
BS
2
IN
3
SW
4
5
6
7
8
Description
High-Side Gate Drive Boost Input. BS supplies the drive for the high-side N-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 4.3V to 7V 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 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. The Exposed Pad and GND pin must be connected to the same ground plane.
Exposed Pad
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
COMP
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 high to
EN
turn on the regulator, drive it low to turn it off. Pull up with 100kΩ resistor to IN for
automatic startup.
Soft-start Control Input. SS controls the soft-start period. Connect a capacitor from SS
SS
to GND 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.
MP9403 Rev.0.9
4/12/2016
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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL PERFORMANCE CURVES
VIN=5V, VOUT=2.5V, CIN=10μF×2, COUT=22uF×2, L=6.8μH, CSS=0.1μF, TA=25°C, unless otherwise
noted.
Efficiency vs.
Load Current
100
90
Efficiency vs.
Load Current
VOUT=1.8V
100
90
VIN=4.3V
VIN=5V
80
80
70
VIN=7V
60
EFFICIENCY
EFFICIENCY
VOUT=3.3V
VIN=5V
50
40
30
70
50
40
30
20
20
10
0
0.01
10
0
0.1
1
10
VIN=7V
60
0.01
0.1
1
10
LOAD CURRENT(A)
LOAD CURRENT(A)
Output Ripple Voltage
Output Ripple Voltage
Enable Startup
IO=0A
IO=3A
IO=0A
VO/AC
10mV/div.
VO/AC
10mV/div.
VSW
5V/div.
VSW
5V/div.
Iinductor
0.5A/div.
VO
1V/div.
VEN
5V/div.
VSW
5V/div.
Iinductor
1A/div.
Iinductor
2A/div.
Enable Startup
Enable Shutdown
Enable Shutdown
IO=3A
IO=0A
IO=3A
VO
1V/div.
VEN
5V/div.
VO
1V/div.
VEN
5V/div.
VSW
5V/div.
VSW
5V/div.
VO
1V/div.
VEN
5V/div.
VSW
5V/div.
Iinductor
2A/div.
Iinductor
1A/div.
Iinductor
2A/div.
MP9403 Rev.0.9
4/12/2016
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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
BLOCK DIAGRAM
IN
+
VOUT
CURRENT
SENSE
AMPLIFIER
OVP
0.95V
-OSCILLATOR
FB
+
250kHz
0.3V
RAMP
BS
----
+
0.8V
5V
--
CLK
+
SS
+
VIN
+
ERROR
AMPLIFIER
S
Q
R
Q
SW
CURRENT
COMPARATOR
VOUT
COMP
GND
EN
OVP
1.2V
IN < 3.65V
IN
--
1.3 V
+
INTERNAL
REGULATORS
SHUTDOWN
COMPARATOR
Figure 1—Function Block Diagram
OPERATION
FUNCTIONAL DESCRIPTION
The MP9403 is a fully-integrated synchronous
current-mode step-down regulator. It regulates
input voltages from 4.3V to 7V down to an
output voltage as low as 0.80V, and supplies up
to 3A of load current.
The MP9403 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 with the switch current
measured internally to control the output
voltage.
MP9403 Rev.0.9
4/12/2016
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 MP9403 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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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS 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
larger value inductor will have a larger physical
size, higher series resistance, and/or lower
saturation current. A good rule for determining
the inductance value is to allow the peak-to-peak
ripple current in the inductor to be approximately
30% of the maximum switching current limit. Also,
make sure that the peak inductor current is below
the maximum switch current limit. The inductance
value can be calculated by:
L=
Thus the output voltage is:
VOUT = 0.80 ×
R1 + R2
R2
Where VFB is the feedback voltage and VOUT is
the output voltage.
R2 can be as high as 100kΩ, but a typical value
is 10kΩ. Using that value, R1 is determined by:
⎞
V
VOUT ⎛
× ⎜1 − OUT ⎟⎟
fS × ΔI ⎜⎝
VIN ⎠
Where VIN is the input voltage, fS is the 250kHz
switching frequency, and ΔIL is the peak-to-peak
inductor ripple current.
Choose an inductor that will not saturate under
the maximum inductor peak current. The peak
inductor current can be calculated by:
⎛
V
VOUT
× ⎜⎜1 − OUT
VIN
2 × fS × L ⎝
R1 = 12.5 × ( VOUT − 0.80)(kΩ)
ILP = ILOAD +
For example, for a 3.3V output voltage, R2 is
10kΩ, and R1 is 31.6kΩ.
Where ILOAD is the load current.
Inductor
The inductor is required to supply constant
current to the output load while being driven by
the switched input voltage. A larger value
inductor will result in less ripple current that will
result in lower output ripple voltage. However, the
⎞
⎟⎟
⎠
Table 1 lists a number of suitable inductors from
various manufacturers. The choice of which style
inductor to use mainly depends on the price vs.
size requirements and any EMI requirement.
Table 1—Inductor Selection Guide
Inductance (µH)
Max DCR (Ω)
Current Rating (A)
Dimensions
L x W x H (mm3)
744777004
4.7
0.040
4.0
7.3x7.3x4.5
7440650068
6.8
0.033
3.6
10x10x2.8
744066100
10
0.035
3.6
10x10x3.8
VLF10040T-4R7N5R4
4.7
0.015
5.4
10x9.7x4
VLF10040T-6R8N4R5
6.8
0.023
4.5
10x9.7x4
VLF10040T-100M3R8
10
0.033
3.8
10x9.7x4
Part Number
Wurth Electronics
TDK
Toko
1010ASW-4R7M
4.7
0.015
4.4
12.3x12.3x4.5
B992AS-6R8N
6.8
0.028
3.8
8.3x8.3x6.8
1010ASW-100M
10
0.022
3.6
12.3x12.3x4.5
MP9403 Rev.0.9
4/12/2016
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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
Optional Schottky Diode
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
Voltage/Current
Part Number
Rating
B320
20V, 3A
B320A
20V, 3A
SS32
20V, 3A
Vendor
Diodes, Inc.
Diodes, Inc.
Vishay, Inc.
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 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 ×
VOUT
V
× (1 − OUT )
VIN
VIN
The worst-case condition occurs at VIN = 2VOUT,
where:
I C1 =
ILOAD
2
For simplification, choose an input capacitor with
an 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:
MP9403 Rev.0.9
4/12/2016
ΔVIN =
⎛
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:
ΔVOUT =
VOUT ⎛
V
× ⎜⎜1 − OUT
fS × L ⎝
VIN
⎞
⎞ ⎛
1
⎟
⎟⎟ × ⎜ R ESR +
⎜
8 × f S × C2 ⎟⎠
⎠ ⎝
Where C2 is the output capacitance value and RESR
is the equivalent series resistance (ESR) value of
the output capacitor.
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 =
⎛
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 =
VOUT ⎛
V
⎞
× ⎜1 − OUT ⎟⎟ × R ESR
f S × L ⎜⎝
VIN ⎠
The characteristics of the output capacitor also
affect the stability of the regulation system. The
MP9403 can be optimized for a wide range of
capacitance and ESR values.
Compensation Components
MP9403 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 ×
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VFB
VOUT
8
MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
Where AVEA is the error amplifier voltage gain,
400V/V;
GCS
is
the
current
sense
transconductance, 7.0A/V; 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
2π × C3 × A VEA
fP2 =
1
2π × C2 × R LOAD
Where GEA is the error amplifier transconductance,
820μA/V, 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
=
2π × C3 × R3
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 =
1
2π × C2 × R ESR
In this case, a third pole set by the compensation
capacitor (C6) and the compensation resistor (R3)
is used to compensate the effect of the ESR zero
on the loop gain. This pole is located at:
fP 3 =
1
2π × 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 MP9403 is 250kHz, so the desired
crossover frequency is 25kHz.
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.
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 =
2π × C2 × f C VOUT
×
G EA × G CS
VFB
Where fC is the desired crossover frequency,
25kHz.
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
2π × R3 × f C
Table 3—Compensation Values for Typical
Output Voltage/Capacitor Combinations
VOUT
L
1.2V
4.7uH
1.8V
6.8μH
2.5V
6.8μH
3.3V
6.8μH
C2
22μFx2
Ceramic
22μFx2
Ceramic
22μFx2
Ceramic
22μFx2
Ceramic
R3
C3
C6
2.4kΩ 6.8nF None
4.3kΩ 6.8nF None
6.8kΩ 4.7nF None
8.2kΩ 2.2nF None
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 250kHz switching frequency,
or the following relationship is valid:
f
1
< S
2π × C2 × R ESR
2
MP9403 Rev. 0.9
4/12/2016
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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
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:
C6 =
C2 × R ESR
R3
External Bootstrap Diode
An external bootstrap diode may enhance the
efficiency of the regulator, the applicable
conditions of external BST diode are:
z
VOUT is 5V or 3.3V; and
z
Duty cycle is high: D=
MP9403 Rev.0.9
4/12/2016
VOUT
>65%
VIN
In these cases, an external BST diode is
recommended from the output of the voltage
regulator to BST pin, as shown in Fig.2
MP9403
Figure 2—Add Optional External Bootstrap
Diode to Enhance Efficiency
The recommended external BST diode is IN4148.
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MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS STEP-DOWN CONVERTER
TYPICAL APPLICATION CIRCUITS
INPUT
4.3V to 7V
7
8
2
IN
EN
1
BS
3
SW
MP9403
SS
GND
FB
COMP
4
OUTPUT
1.8V
3A
5
D1
B320
(optional)
6
C6
(optional)
Figure 3—MP9403 with 1.8V Output Typical Application Schematic
INPUT
5V to 7V
7
8
2
IN
EN
1
BS
3
SW
MP9403
SS
GND
FB
COMP
4
6
C6
(optional)
OUTPUT
3.3V
3A
5
D1
B320
(optional)
Figure 4—MP9403 with 3.3V Output Typical Application Schematic
MP9403 Rev. 0.9
4/12/2016
www.MonolithicPower.com
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
11
MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS 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 5 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
R4
2
7
8
C1
1
IN
BS
SW
EN
MP9403
SS
GND
4
FB
COMP
OUTPUT
R1
5
6
C3
C4
L1
3
D1
(optional)
R2
C2
R3
MP9403 Typical Application Circuit
R3
COMP 6
3 SW
FB 5
EN 7
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 5—MP9403 Typical Application Circuit and PCB Layout Guide
MP9403 Rev.0.9
4/12/2016
www.MonolithicPower.com
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
12
MP9403 – 3A, 7V, 250kHz INTEGRATED SYNCHRONOUS 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
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.
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.
MP9403 Rev.0.9
4/12/2016
www.MonolithicPower.com
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
13