MP3415 [MPS]
3.6A, 1MHz, Synchronous, Step-Up Converter with Output Disconnect;
| 型号： | MP3415 |
| 厂家： | 
MONOLITHIC POWER SYSTEMS |
| 描述： | 3.6A, 1MHz, Synchronous, Step-Up Converter with Output Disconnect |
| 文件： | 总17页 (文件大小：673K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MP3415
3.6A, 1MHz, Synchronous, Step-Up
Converter with Output Disconnect
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP3415 is a high-efficiency, synchronous,
current-mode, step-up converter with output
disconnect.
1.8V to 5.5V Input Voltage Range
Output Voltage up to 5.5V
Supports 5V/1.5A at 2.8V Input
Internal Synchronous Rectifier
1MHz Fixed Switching Frequency
22μA Quiescent Current
<1μA Shutdown Current
True Output Disconnect from the Input
Efficiency up to 97%
Internal Compensation, Inrush Current
Limiting, and Internal Soft Start
Small External Components
Protection Features Include OVP, SCP, and
OTP
The MP3415 can start up with an input voltage
as low as 1.8V while providing inrush current
limiting and output short-circuit protection
(SCP). The integrated, P-channel, synchronous
rectifier improves efficiency and eliminates the
need for an external Schottky diode. The P-
channel MOSFET disconnects the output from
the input when the MP3415 shuts down. Output
disconnect discharges the output completely,
allowing the MP3415 to draw a supply current
below 1μA in shutdown mode.
Small QFN-12 (2mmx2mm) Package
The 1MHz switching frequency allows small
external
components
while
internal
APPLICATIONS
compensation and soft start minimize the
external component count, making the MP3415
a compact solution for a wide current load
range.
Two-Cell and Three-Cell Alkaline, NiCd or
NiMH, or Single-Cell Li Battery Consumer
Products
Personal Medical Devices
Portable Media Players
Wireless Peripherals
The MP3415 features an integrated power
MOSFET that supports an output up to 5.5V
and a peak switching current above 3.6A.
Gaming Accessories
The MP3415 is available in a small QFN-12
(2mmx2mm) package.
All MPS parts are lead-free, halogen-free, and adhere to the RoHS directive. For
MPS green status, please visit the MPS website under quality assurance. “MPS”
and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
TYPICAL APPLICATION
Efficiency vs.
Load Current
VOUT=5V
100
L1
R4
C3
1.5μH
1Ω
1nF
SW
VIN
VOUT
IN
OUT
90
C1
10μF
C2
22μF
VIN=3.3V
R1
1MΩ
MP3415
80
VIN=4.2V
FB
OFF
ON
EN
PGND
V
IN=2.8V
70
60
50
R2
137kΩ
AGND
0
0.3
0.6
0.9
1.2
1.5
LOAD CURRENT(A)
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
1
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
ORDERING INFORMATION
Part Number*
Package
Top Marking
MP3415GG
QFN-12 (2mmx2mm)
See Below
* FOR TAPE & REEL, ADD SUFFIX –Z (E.G. MP3415GG–Z)
TOP MARKING
EA: Product code of MP3415GG
Y: Year code
LLL: Lot number
PACKAGE REFERENCE
TOP VIEW
QFN-12 (2mmx2mm)
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
2
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
Thermal Resistance (5)
QFN-12 (2mmx2mm)...............80 ..... 16... °C/W
θJA
θJC
ABSOLUTE MAXIMUM RATINGS (1)
SW, OUT ....................................-0.3V to +6.5V
SW (<5ns) ...................................-0.3V to +9.5V
All other pins................................-0.3V to +6.5V
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-to-
ambient 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 produces an excessive die temperature, causing
the regulator to go into thermal shutdown. Internal thermal
shutdown circuitry protects the device from permanent
damage.
(2)
Continuous power dissipation (TA = +25°C)
................................................................. 1.56W
Junction temperature................................150°C
Lead temperature .....................................260°C
Storage temperature................ -65C to +150°C
Recommended Operating Conditions (3)
Supply voltage (VIN) ........................1.8V to 5.5V
VOUT.............................VIN-MAX x 110% to 5.5V (4)
Operating junction temp. (TJ)....-40°C to +125°C
3) The device is not guaranteed to function outside of its
operating conditions.
4) If VIN is close to VOUT, the boost converter may trigger the
minimum on time. When VIN is higher than VOUT, the boost
converter switches between boost mode and linear charge
mode. Both conditions result in a VOUT-RIPPLE that is too high
and are therefore not recommended.
5) Measured on JESD51-7, 4-layer PCB.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
3
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
ELECTRICAL CHARACTERISTICS
VIN = VEN = 3.3V, VOUT = 5V, TJ = -40°C to 125°C. Typical value is tested at TJ = 25°C,
unless otherwise noted.
Parameters
Symbol Condition
Min
Typ Max Units
Voltage Range
VEN = VIN = 3.3V, VOUT = 5V,
no load, VFB = 0.65V,
measured on OUT, TJ = 25°C
22
8
30
12
µA
µA
Quiescent current
IQ
VEN = VIN = 3.3V, VOUT = 5V,
no load, VFB = 0.65V,
measured on IN, TJ = 25°C
VEN = VOUT = 0V,
measured on IN, TJ = 25°C
Shutdown current
ISD
0.1
1.65
100
1
µA
V
IN under-voltage lockout
VIN UVLO VIN rising, TJ = 25°C
1.7
IN under-voltage lockout
hysteresis
mV
Step-Up Converter
Operation frequency
FSW
0.8
594
591
1.0
600
600
1
1.2
606
609
50
MHz
mV
mV
nA
TJ = 25°C
VFB
Feedback voltage reference
TJ = -40°C to 125°C
Feedback input current
NMOS on resistance
NMOS leakage current
PMOS on resistance
PMOS leakage current
Maximum duty cycle
IFB
VFB = 0.63V
RNDS ON
IN LK
RPDS ON
IP LK
70
mΩ
µA
mΩ
µA
%
VSW = 6.5V, TJ = 25°C
VSW = 6.5V, VOUT = 0V, TJ = 25°C
VIN = 4V, VOUT = 0V
0.1
90
1
1
0.1
95
DMAX
85
0.3
A
Start-up current limit
IST_LIMIT
ISW LIMIT
VIN = 4V, VOUT-setting = 3.6V,
pull VOUT to 3.3V
0.8
4.2
A
A
NMOS current limit
Logic Interface
Duty = 40%
3.6
1.2
5
EN input high-level voltage
EN input low-level voltage
EN input current
VEN H
VEN L
IEN
V
V
0.4
Connect to VIN
10
nA
Protection
Thermal shutdown(6)
155
25
°C
°C
Over-temperature hysteresis(6)
NOTE:
6) Guaranteed by characterization, not tested in production.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
4
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 3.3V, VOUT = 5V, L = 1.5µH, TA = 25°C, unless otherwise noted.
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
4.6
4.4
4.2
4
Rising
3.8
3.6
3.4
3.2
3
Falling
0
1
2
3
4
5
0
10 20 30 40 50 60 70 80
-50 -25
0
25 50 75 100 125 150
1
5
4.5
4
1
0.8
0.6
0.4
0.2
0
Rising
0.8
0.6
0.4
0.2
0
Falling
3.5
3
-50 -25
0
25 50 75 100 125 150
-50 -25
0
25 50 75 100 125 150
-50 -25
0
25 50 75 100 125 150
605
1100
10
8
1050
1000
950
603
601
599
597
595
6
4
900
2
850
800
-50 -25
0
-50 -25
0
25 50 75 100 125 150
0
25 50 75 100 125 150
1
2
3
4
5
6
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
5
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
Typical Performance Characteristics (continued)
VIN = 3.3V, VOUT = 5V, L = 1.5µH, TA = 25°C, unless otherwise noted.
24
22
20
18
16
14
12
10
1
2
3
4
5
6
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
6
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
VIN = 3.3V, VOUT = 5V, L = 1.5µH, TA = 25°C, unless otherwise noted.
Efficiency vs.
Load Current
VOUT=5V
Efficiency vs.
Load Current
VOUT=3.3V
Load Regulation
VOUT=5V
1
0.8
0.6
0.4
0.2
0
100
90
80
70
60
50
100
90
80
70
60
50
V
IN=3.3V
VIN=4.2V
V
IN=3V
VIN=4.2V
VIN=1.8V
VIN=2.5V
VIN=2.8V
-0.2
-0.4
-0.6
-0.8
-1
V
IN=3.3V
VIN=2.8V
0
0.3
0.6
0.9
1.2
1.5
0
0.3
0.6
0.9
1.2
1.5
0
0.25 0.5 0.75
1 1.25 1.5 1.75
LOAD CURRENT(A)
LOAD CURRENT(A)
LOAD CURRENT(A)
Line Regulation
VOUT=5V
Bode Plot
VIN=3.3V, VOUT=5V, IOUT=1.5A
Load Capability
vs. Input Voltage (7)
VOUT=5V
1
0.8
0.6
0.4
0.2
0
60
40
20
0
180
3
2.5
2
IOUT=0A
Phase
120
60
IOUT=0.75A
IOUT=1.5A
1.5
1
0
-0.2
-0.4
-0.6
-0.8
-1
-20
-40
-60
-60
-120
-180
Gain
0.5
0
1.5
1.5
2.5
3.5
4.5
5.5
1
10
100
1000
2
2.5
3
3.5
4
4.5
5
INPUT VOLTAGE (V)
FREQUENCY(kHz)
INPUT VOLTAGE (V)
Case Temperature Rise
vs. Load Current
VOUT=5V
50
40
30
20
10
0
VIN=3V
V
IN=3.3V
VIN=4.2V
1.5
0
0.5
1
2
LOAD CURRENT(A)
NOTE:
7) Tested with a 3.6A inductor peak current with the schematic shown in Figure 3. The maximum load current may decrease if the
temperature rising is limited on the real application board.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
7
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
VIN = 3.3V, VOUT = 5V, L = 1.5µH, TA = 25°C, unless otherwise noted.
Steady State
Steady State
V
Start-Up
IN
I
= 0A
I
= 1.5A
I
= 0A
OUT
OUT
OUT
V
/AC
V
/AC
OUT
OUT
50mV/div.
50mV/div.
V
OUT
2V/div.
V
V
IN
IN
2V/div.
2V/div.
V
IN
V
SW
V
SW
2V/div.
5V/div.
5V/div.
V
SW
5V/div.
I
I
I
L
L
L
1A/div.
1A/div.
2A/div.
V
Shutdown
IN
I
= 0A
OUT
V
V
V
OUT
OUT
OUT
2V/div.
2V/div.
IN
2V/div.
2V/div.
V
V
IN
2V/div.
V
IN
V
2V/div.
SW
V
SW
V
5V/div.
SW
5V/div.
5V/div.
I
I
I
L
L
L
1A/div.
1A/div.
1A/div.
EN Start-Up
EN Shutdown
I
= 0A
I
= 0A
OUT
OUT
V
V
V
OUT
OUT
OUT
2V/div.
2V/div.
2V/div.
V
EN
2V/div.
V
V
EN
EN
2V/div.
2V/div.
V
V
SW
SW
V
SW
5V/div.
5V/div.
5V/div.
I
I
I
L
L
L
1A/div.
1A/div.
1A/div.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
8
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
VIN = 3.3V, VOUT = 5V, L = 1.5µH, TA = 25°C, unless otherwise noted.
V
V
V
OUT
OUT
OUT
2V/div.
2V/div.
2V/div.
V
EN
2V/div.
V
V
IN
IN
2V/div.
2V/div.
V
V
V
SW
SW
SW
5V/div.
5V/div.
5V/div.
V
/AC
OUT
500mV/div.
V
V
OUT
OUT
2V/div.
2V/div.
V
V
IN
IN
2V/div.
2V/div.
V
V
SW
SW
5V/div.
5V/div.
I
OUT
500mA/div.
I
I
L
L
1A/div.
1A/div.
V
/AC
OUT
500mV/div.
I
OUT
500mA/div.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
9
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
PIN FUNCTIONS
Pin #
Name Description
PGND Power Ground.
1, 10
Power Switch Output. SW is the connection node of the internal low-side MOSFET and
synchronous MOSFET. Connect the power inductor between SW and the input power. Keep
the PCB trace length as short and wide as possible to reduce EMI and voltage spikes.
2, 11
3, 12
SW
Output. OUT is the drain of the internal synchronous rectifier MOSFET. Bias power is
derived from OUT once VOUT exceeds VIN. PCB trace length from OUT to the output filter
capacitor(s) should be as short and wide as possible. The output disconnect feature allows
OUT to be completely disconnected from IN when EN is low.
OUT
Power Supply Input. The start-up bias is derived from IN and must be bypassed locally.
The bias power is derived from OUT once VOUT exceeds VIN.
4
5
6
IN
N/C
EN
No Connection.
Chip Enable Control Input. Set EN higher than 1.2V to turn on the regulator. Set EN lower
than 0.4V to turn off the regulator.
Feedback. Connect FB to the tap of an external resistive voltage divider from the output to
set the output voltage.
7
FB
8
9
AGND Analog Ground.
TRIM Test Pin for Factory Use Only. Connect TRIM to GND during application.
MP3415 Rev. 1.0
3/29/2016
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10
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
BLOCK DIAGRAM
VIN
L1
C1
PGND
SW
IN
Enable
EN
Bias and
Voltage Ref
VIN
OFF
ON
Body
Control
VMAX
VDD
VOUT
OVP
OUT
HS
Thermal
Control
C2
Current Sense
Driver and
Control Logic
OUT
Start-Up
Mode Control
R1
PGND
LS
PGND
Current
Limit
Oscillator
S
Current Sense
Amplifier
+
-
Slope
PGND
COMP
FB
+
-
+
+
PWM
COMP
-
EA
Soft Start
R2
AGND
0.6V
Clamp
PGND
Figure 1: Functional Block Diagram
MP3415 Rev. 1.0
3/29/2016
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11
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
Device Enable (EN)
OPERATION
The device begins operating if EN is higher
The MP3415 is a 1MHz, synchronous, step-up
converter with true output disconnect. The
device features a fixed-frequency, current-
mode, PWM control for ideal line and load
regulation. The internal soft start and loop
compensation simplify the design process and
minimize external components. The internal
low-RDS(ON) MOSFETs combined with frequency
stretching allow the MP3415 to achieve high
efficiency over a wide load range.
than 1.2V and enters shutdown mode if EN is
lower than 0.4V. In shutdown mode, all internal
control circuits switch off, and the output
disconnects from the input completely.
Power-Save Mode (PSM)
The MP3415 enters power-save mode (PSM)
automatically when the load decreases and
switches back to PWM mode when the load
increases. In PSM, the converter stretches the
frequency down to reduce switching and driver
loss. The switch frequency is also stretched
down when the input voltage is close to the
output voltage, which triggers the minimum on
time if kept at a 1MHz frequency. This helps
decrease the output ripple by avoiding group
pulse mode. Under very light-load conditions,
the MP3415 runs in group-pulse mode to
regulate the output voltage and save more
power.
Start-Up
When enabled, the MP3415 starts up in linear
charge mode. During the linear charge, the
rectified P-channel MOSFET (PMOS) turns on
until the output voltage (VOUT) is charged close
to the input voltage (VIN). To prevent inrush
current, the PMOS current is limited to about
0.3A when VOUT is 0V. The PMOS linear charge
current limit is increased to about 0.8A while
VOUT rises to 3.3V (if VIN is higher than 3.3V).
This circuit helps to limit the output current
under short-circuit conditions. Once the output
voltage reaches VIN, the linear charging period
elapses, and the device begins switching. VOUT
begins rising under internal soft-start (SS)
control. In boost switching condition, the current
limit is 4.2A, typically.
Error Amplifier (EA)
The error amplifier (EA) is an internally
compensated amplifier. The EA compares the
internal 0.6V reference voltage against VFB to
generate an EA signal, which controls VOUT
.
The output voltage of the MP3415 is adjusted
via FB by an external resistor divider and can
be calculated with Equation (1):
When VOUT is higher than VIN, the MP3415
powers its internal circuits from VOUT instead of
VIN. This allows for strong driving capability and
high efficiency, even if VIN drops to as low as
1.8V.
R1
(1)
VOUT 0.6V(1
)
R2
Setting a high value for R1 and R2 can achieve
a low quiescent current. However, a resistance
that is too high is sensitive to noise and leads to
a low loop bandwidth. Set the R1 value
between 499kꢀ and 1Mꢀ for good leakage,
stability, and transient balance.
Soft Start (SS)
The MP3415 provides a soft start (SS) by
charging an internal capacitor with a current
source. During the linear charge period, the SS
signal continues rising, following FB. Once the
linear charge elapses, the voltage on the SS
capacitor is charged and ramps up to the
reference voltage based on the internal fixed
slew rate. The SS capacitor is discharged
completely during a forced shutdown, thermal
shutdown, or output short circuit.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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12
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
Overload (OLP) and Short-Circuit (SCP)
Current Sensing
Protections
In a linear charge condition, the high-side, P-
channel MOSFET current is sensed and
compared with the current limit threshold. The
compared output manages the linear charge
current.
When an overload or a short circuit occurs, the
output voltage drops. If VOUT drops below VIN -
0.3V, the MP3415 stops for about 50µs and
then runs in a linear charge mode. If the
overload or short circuit is removed, the
In boost switching condition, lossless current
sensing converts the N-channel MOSFET
switch current signal to a voltage that is
summed with the internal slope compensation.
The summed signal is compared with the EA
output to provide a peak-current control
command for PWM. The peak switch current is
limited to approximately 4.2A. The switch-
current signal is blanked internally for 60ns to
enhance noise immunity.
MP3415
automatically.
restarts
under
SS
control
Over-Voltage Protection (OVP)
If VOUT is higher than the typical 6V threshold,
the boost switching stops. After the output
drops to about 5.7V, the switching recovers
automatically. This protects the internal power
MOSFET from over-voltage stress.
Thermal Shutdown (TSD)
Output Disconnect
The device has an internal temperature
monitor. If the die temperature exceeds 155°C,
the converter turns off. Once the temperature
drops below 130°C, the converter restarts.
The MP3415 is designed to allow for true output
disconnect
by
eliminating
body
diode
conduction of the internal P-channel MOSFET
rectifier. This allows VOUT to reach 0V during
shutdown, drawing zero current from the input
source. This also allows for inrush current
limiting at start-up, which minimizes the surge
current seen by the input supply. To obtain the
advantages of the output disconnect, there
cannot be an external Schottky diode
connected between SW and VOUT.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
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© 2016 MPS. All Rights Reserved.
13
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
Selecting the Inductor
APPLICATION INFORMATION
The MP3415 utilizes small, surface-mounted
chip inductors for their 1MHz switching
frequencies. Inductor values between 1μH and
2.2μH are suitable for most applications.
Inductors with larger values allow for slightly
greater output current capabilities by reducing
the inductor ripple current. However, a larger
inductance value increases component size.
The minimum inductance value can be
calculated with Equation (3):
Selecting the Input Capacitor
Low equivalent series resistance (ESR) input
capacitors reduce input switching noise and
peak current drawn from the input power.
Ceramic capacitors are recommended for input
decoupling and should be placed as close to
the device as possible. Use a ceramic capacitor
larger than 10μF to limit the VIN ripple.
Output Capacitor Selection
V
IN(MIN) (VOUT(MAX) V
)
IN(MIN)
To ensure stability over the full operating range,
the output capacitor requires a minimum
capacitance value of 22μF at the programmed
output voltage. A higher capacitance value may
be required to lower the output and transient
(3)
L
VOUT(MAX) IL fS
Where ∆IL is the acceptable inductor current
ripple.
ripple.
X5R
or
X7R
capacitors
are
Typically, the inductor current ripple is set to
30% to 50% of the maximum inductor current.
Maintain a low series resistance of the inductor
(DCR) to reduce resistive power loss. The
saturated current (ISAT) should be large enough
to support the peak current.
recommended for their low ESR values.
Supposing the ESR is zero, calculate the
minimum output capacitor value needed to
support the ripple in PWM mode with Equation
(2):
IO (VOUT(MAX) V
)
IN(MIN)
SW RC Snubber
(2)
CO
fS V OUT(MAX)∆V
When the MP3415 is used to generate an
output of 4V or higher, an RC snubber should
be added to protect the internal MOSFET from
over-voltage caused by the SW spike. The
recommended RC snubber parameters are 1ꢀ
and 1nF (see Figure 3).
Where VOUT(MAX) is the maximum output voltage,
VIN(MIN) is the minimum input voltage, IO is the
output current, fS is the switching frequency,
and ∆V is the acceptable output ripple.
A 1μF ceramic capacitor is recommended to be
placed between VOUT and PGND with a short
loop to reduce spikes on the SW node and
improve EMI performance.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
14
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
PCB Layout Guidelines
Efficient PCB layout is critical for high-
frequency switching power supplies. Poor
Top Layer
Bottom Layer
Via
L1
layout can result in reduced performance,
excessive EMI, resistive loss, system instability,
and even over-voltage stress. For best results,
refer to Figure 2 and follow the guidelines
below:
U1
R3
C1
C2B
R4
R1 R2
C3
1. Place the output capacitor as close to OUT
as possible with minimal distance to PGND.
2. Place a small decoupling capacitor in
parallel with the bulk output capacitor and
with smaller loop than bulk output capacitor.
This is very important for reducing spikes on
SW and improving EMI performance.
Figure 2: Layout Recommendation
Design Example
Table 1 shows a design example following the
application guidelines for the following
specifications:
3. Place the input capacitor and inductor as
close to IN and SW as possible.
Table 1: Design Example
4. Keep the trace between the inductor and
SW as wide and short as possible.
VIN
VOUT
IOUT
2.8V - 4.5V
5V
0A - 1.5A
5. Keep the feedback loop far away from all
noise sources, such as SW.
The typical application circuit in Figure 3 is for
5V VOUT It shows the detailed application
schematic and the basis for the typical
performance waveforms. For additional detailed
device applications, please refer to the related
evaluation board datasheet (EVB).
6. Place the feedback divider resistors as
close to FB and AGND as possible.
.
7. Tie the ground return of the input/output
capacitors as close to PGND as possible.
8. Use a large copper GND area. Vias around
GND are recommended to lower the die
temperature.
9. Add an RC snubber circuit from SW to
PGND to reduce the SW spike when the
output is higher than 4V.
See Figure 2 for layout recommendations.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
15
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
TYPICAL APPLICATION CIRCUITS
Figure 3: Typical Boost Application Circuit, VIN = 2.8V to 4.5 V, VOUT = 5V, IOUT = 0A - 1.5A
L1 1.5μH
VOUT
SW
IN
OUT
FB
C2B
1μF
C2A
22μF
R1
1MΩ
U1
MP3415
VIN
GND
GND
R2
220kΩ
C1
10μF
R3
100k
EN
AGND
GND
GND
GND
Figure 4: Typical Boost Application Circuit, VIN = 1.8V to 3V, VOUT = 3.3V, IOUT = 0A - 1.5A(8)
8) Tested with a 3.6A inductor peak current with the schematic shown in Figure 4. The maximum load current may decrease if VIN drops to
lower than 2.1V.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
16
MP3415—3.6A, 1MHz STEP-UP CONVERTER WITH OUTPUT DISCONNECT
PACKAGE INFORMATION
QFN-12 (2MMX2MM)
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.
MP3415 Rev. 1.0
3/29/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
17
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