MPM3632S
High-Frequency 18V/3A DC/DC Regulator
with Integrated Inductor
DESCRIPTION
FEATURES
The MPM3632S is a synchronous, rectified,
step-down, mini-module regulator with built-in
power MOSFETs, an inductor, and two
capacitors. It offers a compact solution with only
input and output capacitors to achieve a 3A
continuous output current with excellent load and
line regulation over a wide input supply range.
The MPM3632S operates in a fixed 2.2MHz
switching frequency with constant on-time (COT)
control to provide fast load transient response.
Full protection features include output overvoltage protection, over-current protection, and
thermal shut down.
Wide 4V to 18V Operation Input Range
Internally Fixed Soft Start Time
0.5% Accuracy Output Voltage
3A Continuous Output Current
2.2MHz Switching Frequency
Forced CCM Mode
Power Good Indicator
Hiccup OCP Protection
Output Over-Voltage Protection
Fast Transient Response
Available in an EC LGA-10
(3mmx3mmx1.45mm) Package
APPLICATIONS
The device eliminates design and manufacturing
risks while dramatically improving time to market.
The MPM3632S is available in a space-saving
EC LGA-10 (3mmx3mmx1.45mm) package.
Server Systems
Medical and Imaging Equipment
Distributed Power Systems
All MPS parts are lead-free, halogen free, and adhere to the RoHS directive. For
MPS green status, visit the MPS website under Quality Assurance. “MPS”, the
MPS logo, and “Simple, Easy Solutions” are registered trademarks of Monolithic
Power Systems, Inc. or its subsidiaries.
TYPICAL APPLICATION
Efficiency vs. Load Current
VOUT = 3.3V
VIN
C1
EN
VOUT
MPM3632S
EN
90
R4
OUT_S
R1
47kΩ
VCC
FB
AGND
R2
15kΩ
PG
PGND
100
VOUT
3.3V
C3
C2
EFFICIENCY (%)
4V to 18V
VIN
80
70
60
VIN=4V
VIN=12V
VIN=18V
50
40
0
0.5
1
1.5
2
LOAD CURRENT (A)
MPM3632S Rev. 1.03
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11/27/2020
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2.5
3
1
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
ORDERING INFORMATION
Part Number*
MPM3632SGPQ
Package
Top Marking
EC LGA-10
See Below
(3mmx3mmx1.45mm)
* For Tape & Reel, add suffix –Z (e.g. MPM3632SGPQ–Z).
MSL Rating
3
TOP MARKING
Y: Year code
W: Week code
BPE: part number code
LLL: Lot number
PACKAGE REFERENCE
TOP VIEW
PG VCC AGND
10
9
8
EN
1
7
FB
VIN
2
6
OUT_S
3
4
5
PGND PGND VOUT
EC LGA-10 (3mmx3mmx1.45mm)
MPM3632S Rev. 1.03
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11/27/2020
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2
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
PIN FUNCTIONS
Pin #
Name
Description
1
EN
Enable. Drive EN high to enable the MPM3632S.
2
VIN
Supply voltage. The MPM3632S operates from a 4V to 18V input rail. Requires a ceramic
capacitor to decouple the input rail. Connect using a wide PCB trace.
3, 4
PGND
System ground. Reference ground of the regulated output voltage. Requires special
consideration during PCB layout. Connect to GND with copper traces and vias.
5
VOUT
Power output pin.
6
OUT_S
7
8
FB
AGND
Output voltage sense pin.
Feedback pin. Set the output voltage with divider resistors.
9
VCC
10
PG
Analog ground.
Internal 3.3V LDO regulator output. The MPM3632S does not require external
connections due to its internal decoupling capacitor .
Power good output. Open-drain structure. PG switches to an open-drain state when FB
is greater than 90%. It switches to low if FB is below 80% of VREF.
θJA
θJC
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance (4)
VIN …………………………………..-0.3V to +20V
VSW………………………-0.3V (-5V for < 10ns)
to VIN + 0.7V (22V for < 10ns)
VBST……………………………………… VSW + 4V
VEN……………………………………………...18V
VOUT .............................................................6.5V
VPG...............................................................5.5V
All other pins...................................-0.3V to +4V
Continuous power dissipation (TA = +25°C) (2)
……………………………………………….2.08W
Junction temperature………………………150°C
Lead temperature……………………….….260°C
Storage temperature ……….….-65°C to +150°C
EVM3632S-PQ-00A.........…..60 ........ 30... °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 EVM3632S-PQ-00A, 4-layer PCB.
ESD Rating
Human-body model (HBM) .......................... 2kV
Charged-device model (CDM) .................... 1kV
Recommended Operating Conditions (3)
Supply voltage VIN ……………..………4V to 18V
Output voltage VOUT ………………...0.8V to 5.2V
Operating junction temp. (TJ). .. -40°C to +125°C
MPM3632S Rev. 1.03
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11/27/2020
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3
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
ELECTRICAL CHARACTERISTICS
VIN = 12V, TA = -40°C to +125°C (5), unless otherwise noted.
Parameter
Symbol
Condition
Supply current (shutdown)
IIN
VEN = 0V
Supply current (quiescent)
Iq
No switching, FB = 0.85V
Switch leakage
SWLKG
Switching frequency
Low-side valley current limit (6)
ILIMIT1
Low-side negative current limit
ILIMIT2
Minimum on time (6)
tON_MIN
Minimum off time (6)
tOFF_MIN
Reference accuracy
VREF
Output load regulation (6)
VOLDREG
Output line regulation (6)
VOLNREG
Output over-voltage threshold
OVP hysteresis
OVP delay
Output pin absolute OV
VOVP
VEN = 0V, VSW = 12V
VOUT = 3.3V
VOUT = 1.2V
Min
-15%
-15%
3
788
Same behavior with FB >
115%
Units
15
μA
μA
2200
2200
3.3
1
+15%
+15%
3.9
μA
kHz
kHz
A
-2.5
A
25
ns
80
ns
812
mV
-0.5
+0.5
%
-0.5
+0.5
%
120%
VREF
110%
800
115%
5%
2
tOVP
VOVP2
Max
1200
Force PWM mode or OVP,
need force PWM option
Reach min tON, then
decrease
fSW.
Avoid
unstable pulse. Simulate
18V to 1V spec.
Reach min tOFF then
decrease fSW, simulate 4.2V
to 3.3V spec.
TJ = -40°C to +125°C
VOUT = 3.3V,
IOUT = 0A to 3A
VOUT = 3.3V,
IO = 0.1A/1.5A/3A
FB pin OV threshold,
monitor Vin OV then hiccup
OVP is disabled during SS
Typ
5.7
Absolute OV hysteresis
6
VREF
μs
6.3
50
PG OV threshold rising
PGOVHi
Fault
PG OV threshold falling
PGOVLo
Good
PG UV threshold rising
PGUVHi
Good
PG UV threshold falling
PGUVLo
Fault
Power good deglitch time
PGDeg
110%
115%
mV
120%
110%
85%
90%
V
VREF
VREF
95%
VREF
80%
VREF
50
μs
MPM3632S Rev. 1.03
www.MonolithicPower.com
11/27/2020
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4
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
ELECTRICAL CHARACTERISTICS (continued)
VIN = 12V, TA = -40°C to +125°C (5), unless otherwise noted.
Parameter
PG sink current capability
EN rising threshold
EN falling threshold
VIN UVLO rising
VIN UVLO hysteresis
VCC regulator
VCC load regulation
Soft start time (6)
Thermal shutdown (6)
Thermal hysteresis (6)
Symbol Condition
VPG
Sink 4mA
VEN_RISI
NG
VEN_FALL
INUVVth
INUVHYS Take care VCC LDO dropout
VCC
ICC = 20mA
tSS
VOUT from 10% to 90%
Min
Typ
0.4
Max
0.6
Units
V
1.1
1.20
1.3
V
0.96
3.2
1.00
3.6
500
3.3
3
1.65
150
20
1.04
3.9
V
V
mV
V
%
ms
°C
°C
Notes:
5) Not tested in production and guaranteed by over-temperature correlation.
6) Guaranteed by characterization, not production tested.
MPM3632S Rev. 1.03
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11/27/2020
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5
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS
Performance waveforms are tested on the evaluation board of the Design Example section.
VIN = 12V, VOUT = 3.3V, TA = 25°C, unless otherwise noted.
Efficiency vs. Load Current
Efficiency vs. Load Current
VOUT = 3.3V
100
100
90
90
EFFICIENCY (%)
EFFICIENCY (%)
VOUT = 5V
80
70
60
VIN=18V
80
70
VIN=12V
50
50
40
40
0
0.5
1
1.5
2
LOAD CURRENT (A)
2.5
3
0
0.5
1.5
2
2.5
3
Load Regulation vs. Load Current
Load Regulation vs. Load Current
VOUT = 5V
VOUT = 3.3V
0.1
LOAD REGULATION (%)
0.06
0.04
0.02
0
-0.02
-0.04
VIN=18V
VIN=12V
-0.06
-0.08
0.05
0
-0.05
VIN=12V
VIN=18V
VIN=4V
-0.1
-0.15
0
0.5
1
1.5
2
2.5
3
0
0.5
LOAD CURRENT (A)
1
1.5
2
2.5
3
LOAD CURRENT (A)
Line Regulation vs. Input Voltage
Temperature Rise vs. Load Current
VIN = 12V, VOUT = 3.3V
VIN = 12V
0.04
60
0.02
0
-0.02
Io=0.01A
Io=1.5A
Io=3A
-0.04
-0.06
-0.08
TEMPERATURE RISE (℃)
LINE REGULATION (%)
1
LOAD CURRENT (A)
0.08
LOAD REGULATION (%)
VIN=4V
VIN=18V
VIN=12V
60
50
40
30
20
VOUT=3.3V
VOUT=5V
10
0
4
5
6
7
8
9
10 11 12 13 14
INPUT VOLTAGE (V)
0
0.5
1
1.5
2
2.5
3
LOAD CURRENT (A)
MPM3632S Rev. 1.03
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11/27/2020
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MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS
Performance waveforms are tested on the evaluation board of the Design Example section.
VIN = 12V, VOUT = 3.3V, TA = 25°C, unless otherwise noted.
Thermal Derating
VIN = 12V
LOAD CURRENT (A)
3
2.5
2
1.5
1
Vout=1V
Vout=1.8V
Vout=3.3V
Vout=5V
0.5
0
0
10 20 30 40 50 60 70 80 90 100
AMBIENT TEMPERATURE (℃)
MPM3632S Rev. 1.03
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11/27/2020
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MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Performance waveforms are tested on the evaluation board of the Design Example section.
VIN = 12V, VOUT = 3.3V, TA = 25°C, unless otherwise noted.
VO Ripple
VO Ripple
IOUT = 0A
IOUT = 3A
CH1:
VOUT/AC
20mV/div.
CH1:
VOUT/AC
20mV/div.
CH3: VSW
10V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
5A/div.
200ns/div.
200ns/div.
VIN Start-Up through Input Voltage
VIN Start-Up through Input Voltage
IOUT = 0A
IOUT = 3A
CH1: VOUT
2V/div.
CH1: VOUT
2V/div.
CH2: VIN
5V/div.
CH3: VSW
10V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
5A/div.
5ms/div.
1ms/div.
Shutdown through Input Voltage
Shutdown through Input Voltage
IOUT = 0A
IOUT = 3A
CH1: VOUT
2V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH1: VOUT
2V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
5A/div.
50ms/div.
50ms/div.
MPM3632S Rev. 1.03
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11/27/2020
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8
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Performance waveforms are tested on the evaluation board of the Design Example section.
VIN = 12V, VOUT = 3.3V, TA = 25°C, unless otherwise noted.
Start-Up through Enable
Start-Up through Enable
IOUT = 0A
IOUT = 3A
CH1: VOUT
2V/div.
CH1: VOUT
2V/div.
CH2: VEN
5V/div.
CH3: VSW
10V/div.
CH2: VEN
5V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
5A/div.
2ms/div.
2ms/div.
Shutdown through Enable
Shutdown through Enable
IOUT = 0A
IOUT = 3A
CH1: VOUT
2V/div.
CH1: VOUT
2V/div.
CH2: VEN
5V/div.
CH3: VSW
10V/div.
CH2: VEN
5V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
5A/div.
20ms/div.
50μs/div.
Short Circuit Entry
Short Circuit Entry
IOUT = 0A
IOUT = 3A
CH1: VOUT
2V/div.
CH1: VOUT
2V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
5A/div.
10ms/div.
10ms/div.
MPM3632S Rev. 1.03
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11/27/2020
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MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Performance waveforms are tested on the evaluation board of the Design Example section.
VIN = 12V, VOUT = 3.3V, TA = 25°C, unless otherwise noted.
Short Circuit Recovery
Short Circuit Recovery
IOUT = 0A
IOUT = 3A
CH1: VOUT
2V/div.
CH1: VOUT
2V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
5A/div.
10ms/div.
10ms/div.
Short Circuit Steady State
Transient Response
IOUT = 1.5A to 3A, 800mA/μs
CH1:
VOUT/AC
20mV/div.
CH1: VOUT
2V/div.
CH2: VIN
10V/div.
CH3: VSW
10V/div.
CH4: IL
5A/div.
CH4: IL
2A/div.
10ms/div.
100μs/div.
MPM3632S Rev. 1.03
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11/27/2020
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10
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
FUNCTIONAL BLOCK DIAGRAM
VIN
Current Sense
Amplifier
REF
Bias &
Voltage
Reference
EN
3.3V
LDO
VCC
AGND
Bootstrap
Regulator
EA
SS
On
Timer
COMP
Internal
Ramp
HS
Driver
Main
Switch
(NCH)
FB
Logic
OUT_S
PG
0.68uH
VCC
PG
and
OVP
0.92V/0.88V
LS
Driver
Synchronous
Rectifier
(NCH)
OUT
Current
Modulator
0.72V/0.64V
GND
Figure 1: Functional Block Diagram
MPM3632S Rev. 1.03
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MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
OPERATION
PWM Operation
The
MPM3632S
is
a
fully-integrated,
synchronous, rectified, forced CCM mode, stepdown switch mode converter. Constant-on-time
(COT) control provides fast transient response
and easy loop stabilization. At the beginning of
each cycle, the high-side MOSFET (HS-FET)
turns on if the feedback voltage (VFB) drops
below the reference voltage (VREF) due to
insufficient output voltage. The output voltage
and input voltage determine the on period to
ensure the switching frequency stays constant
over the input voltage range.
After the on period elapses, the HS-FET turns off.
It turns on again when VFB drops below VREF.
This repetitive operation regulates the output
voltage. The integrated low-side MOSFET (LSFET) turns on when the HS-FET off to minimize
the conduction loss. There is a dead short
between input and GND if the HS-FET and LSFET turn on simultaneously This is called shootthrough. To avoid shoot-through, a dead time
(DT) is internally generated when the HS-FET is
off and the LS-FET is on, or when the LS-FET is
off and the HS-FET is on.
An internal compensation is applied for COT
control to further stabilize the device. When
ceramic capacitors are used as output
capacitors, this internal compensation then
improves the jitter performance without affecting
the line or load regulation.
Regular-Load Operation
Continuous-conduction mode (CCM) is when the
output current is high and the inductor current is
above 0A. Figure 2 shows CCM operation. When
VFB is below VREF - VDC_ERROR, the HS-FET turns
on for a fixed interval that is set by an internal
one-shot on-timer. When the HS-FET turns off,
the LS-FET turns on until the next period.
In CCM, the switching frequency is constant and
it is also called PWM operation.
Figure 2: Heavy Load Operation
DC Auto Tune Loop
The MPM3632S applies a DC auto-tune loop to
balance the DC error between VFB and VREF. It
adjusts the comparator input-REF to make VFB
follow VREF. This is a slow loop that improves
load and line regulation without affecting the
transient performance. Figure 3 shows the
relationship between VFB, VREF, and REF.
VFB
DC
Error
VREF
REF
Figure 3: DC Auto-Tune Loop Operation
Internal Regulator
A 3.3V internal regulator powers most of the
internal circuitries. When EN is high, this
regulator takes the VIN input and operates in the
full VIN range. When VIN exceeds 3.3V, the output
of the regulator is in full regulation. When VIN is
below 3.3V, the output voltage decreases and
follows the input voltage.
Enable Control
EN is a digital control pin that turns the regulator
on and off. Drive EN high to turn on the regulator;
drive EN low to turn it off. The EN pin is a highvoltage input node, so connect the EN pin to the
input to set auto startup. The EN pin can support
an 18V input voltage.
Under-Voltage Lockout (UVLO)
Under-voltage lockout (UVLO) protects the chip
from operating at an insufficient supply voltage.
The device’s UVLO comparator monitors the
voltage of VIN pin. The UVLO rising threshold is
about 3.6V, and its falling threshold is 3.1V.
MPM3632S Rev. 1.03
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MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
Soft Start
Soft start prevents the converter output voltage
from overshooting during start-up. When the chip
starts, the internal circuitry generates a soft-start
voltage (VSS) that ramps up from 0V to 3.3V.
When VSS is lower than VREF, the error amplifier
uses VSS as the reference. When VSS is higher
than VREF, the error amplifier uses VREF as the
reference.
Over-Current Protection and Hiccup
The device has cycle-by-cycle over-current
limiting control. The current-limit circuit employs
a "valley" current-sensing algorithm. The part
uses the RDS(ON) of the low-side MOSFET to
sense the current. If the current-sense signal
exceeds the current-limit threshold, the PWM
does not initiate a new cycle.
The trip level is fixed internally. The inductor
current is monitored by the voltage between the
GND pin and the SW pin. GND is used as the
positive current sensing node, so connect GND
to the source terminal of the bottom MOSFET.
Since this value is monitored while the high-side
MOSFET is off and the low-side MOSFET is on,
the over-current (OC) trip level sets the valley
level of the inductor current. The load current at
over-current threshold (IOC) can be calculated
with Equation (1):
I
(1)
IOC I _ limit inductor
2
In an over-current condition, the current to the
load exceeds the current to the output capacitor,
and the output voltage falls off. The output
voltage drops until VFB falls below the undervoltage (UV) threshold, which is typically below
50% of VREF. Once UV triggers, the device enters
hiccup mode to periodically restart the part. This
protection mode is especially useful when the
output is dead-shorted to ground, and it greatly
reduces the average short circuit current to
alleviate thermal issues and protect the regulator.
The device exits the hiccup mode when the overcurrent condition is removed.
Over Voltage Protection (OVP)
The MPM3632S monitors the feedback voltage
(VFB) to detect an over-voltage condition. When
VFB exceeds 115% of the reference voltage
(VREF), the controller enters a dynamic regulation
period. During this period, the IC turns the lowside MOSFET on until a -2.5A negative current
limit triggers and turns off the low-side MOSFET
for a fixed delay time if the OV conditions
persists. This discharges the output and
maintains it within the normal range. The part
exits dynamic regulation when VFB falls below
110% of VREF.
If the VOUT pin’s absolute voltage exceeds the
6V threshold, the part enters dynamic regulation
mode to discharge the output voltage.
Thermal Shutdown
Thermal shutdown prevents the chip from
operating at exceedingly high temperatures.
When the silicon die temperatures exceeds
150°C, it shuts down the whole chip. When the
temperature falls below its lower threshold,
(about 130°C), the chip enables again.
PG Indicator
The PG pin is an open-drain output. When VFB is
above the UV threshold and below the OV
threshold, EN is high, VIN is OK, and there is no
over-temperature condition, this pin is set to high
impedance. Otherwise this pin is pulled down to
GND. When an external resistor pulls it up to a
reliable voltage, this pin can be used for the
digital interface.
Floating Driver and Bootstrap Charging
Figure 4 shows an internal bootstrap charging
circuit. An internal bootstrap capacitor powers
the floating power of the MOSFET driver. This
floating driver has its own UVLO protection. This
UVLO’s rising threshold is 2.3V with a hysteresis
of 150mV. The bootstrap capacitor voltage is
regulated internally by VIN through D1, M1, C4,
L1 and C2. If VIN - VSW exceeds 3.3V, U1
regulates M1 to maintain a 3.3V BST voltage
across C4.
VIN
M1
5V
+
-
U1
+
D1
BST
C4
VOUT
SW L1
C2
Figure 4: Internal Bootstrap Charging Circuit
MPM3632S Rev. 1.03
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11/27/2020
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13
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
APPLICATION INFORMATION
Setting the Output Voltage
The external resistor divider sets the output
voltage. Choose the R1 resistance. R2 can be
estimated with Equation (2):
R2
R1
VOUT
(2)
1
0.8V
Figure 5 shows the feedback circuit.
Since the input capacitor absorbs the input
switching current, it requires an adequate ripple
current rating. The RMS current in the input
capacitor can be calculated with Equation (4):
VOUT
R1
MPM3632S
Selecting the Input Capacitor
The input current to the step-down converter is
discontinuous and requires a capacitor 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 with X5R or X7R dielectrics are highly
recommended because of their low ESR and
small temperature coefficients. For most
applications, a 10µF capacitor suffices.
IC1 ILOAD
FB
IC1
Figure 5: Feedback Network
where Vo is the output voltage. The output
voltage feedback gain is determined by:
R2
R1 R2
(3)
To stabilize the system and optimize the load
transient response, place a feed-forward
capacitor (CFF) in parallel with R1. Table 1 shows
the values of feedback resistors and feedforward
capacitors for common output voltages.
Table 1: Common Output Voltages
VOUT
R1
R2
CFF
COUT
(μF)
(V)
(kΩ)
(kΩ)
(pF)
5
47
8.87
39
22
3.3
47
15
39
22
2.5
47
22
39
22
1.8
47
37.4
22
22
1.5
47
53.6
22
22
1.2
47
93.1
22
22
1
47
187
22
22
(4)
The worst-case condition occurs at VIN = 2 x VOUT
shown in Equation (5):
R2
GFB
VOUT VOUT
1
VIN
VIN
ILOAD
2
(5)
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, place a small, high-quality ceramic
capacitor (e.g. 0.1μF) as close to the IC as
possible. When using ceramic capacitors,
ensure that they have enough capacitance to
provide a sufficient charge to prevent an
excessive voltage ripple at the input. The input
voltage ripple caused by the capacitance can be
estimated with Equation (6):
VIN
V
ILOAD
V
OUT 1 OUT
fSW C1 VIN
VIN
(6)
Selecting the Output Capacitor
An output capacitor (C2) is required to maintain
the DC output voltage. Low ESR ceramic
capacitors can be used with the device to
maintain a low output ripple. A 22μF output
ceramic capacitor is sufficient for most cases.
MPM3632S Rev. 1.03
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11/27/2020
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14
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
When using ceramic capacitors, the impedance
at the switching frequency is dominated by the
capacitance. The output voltage ripple is caused
mainly by the capacitance. For simplification, the
output voltage ripple can be estimated with
Equation (7):
ΔVOUT
V
VOUT
1 OUT
2
8 fSW L1 C2
VIN
GND
Top Layer Copper
Bottom Layer Copper
Via
VIN
R1 C3
R4
C1B
ΔVOUT
RESR
C2
C1
(7)
C2B
GND
With tantalum or electrolytic capacitors, the ESR
dominates the impedance at the switching
frequency. For simplification, the output ripple
can be calculated with Equation (8):
VOUT
V
1 OUT
fSW L1
VIN
Top Layer Line
Bottom Layer Line
(8)
R5
C4
R2
R6
R3
VIN
Where L1 is a 0.68µH, integrated inductor.
R1 C3
R4
C1A
The characteristics of the output capacitor also
affect the stability of the regulation system.
PCB Layout Guidelines (7)
Efficient PCB layout is critical for stable
operation. For the best results, see Figure 6 and
follow the guidelines below:
VOUT
Top Layer
C2A
C2B
GND
VOUT
Bottom Layer
Figure 6: Recommended Layout
1. Keep the connection of the input ground and
GND as short and wide as possible.
2. Ensure that all feedback connections are
short and direct.
3. Place the feedback resistors as close as to
the chip as possible.
4. Route sensitive analog areas such as FB
away from SW.
5. Place enough vias around the chip to
improve thermal performance.
Notes:
7)
The recommended layout is based on Figure 6.
MPM3632S Rev. 1.03
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11/27/2020
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15
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
TYPICAL APPLICATION CIRCUIT
VOUT
3.3V/3A
U1
VIN 4V to 18V
VIN
R6
NS
OUT-S
MPM3632S
R4
1kΩ
R1
47kΩ
39pF 22µF 22µF NS
C3 C 2 C2A C2B
EN
R5
100kΩ
PG
C1
10µF
C4
1µF
VCC
PG
FB
PGND
EN
VCC
C1A
10µF
AGND
R3
100kΩ
C1B
0.1µF
OUT
R2
15 kΩ
Figure 8: Typical Application Circuit
MPM3632S Rev. 1.03
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11/27/2020
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16
MPM3632S – SYNCHRONOUS
STEP-DOWN
MINI-MODULE
CONVERTER
PACKAGE OUTLINE
DRAWING FOR
10L ECP
(3X3MM)
MF-PO-D-0xxx revision
PACKAGE INFORMATION
EC LGA-10 (3mmx3mmx1.45mm)
PIN 1 ID
0.15x45°TYP
TOP VIEW
BOTTOM VIEW
SIDE VIEW
0.15X45°
NOTE:
1) ALL DIMENSIONS ARE IN MILLIMETERS.
2) LEAD COPLANARITY SHALL BE x.xx
MILLIMETERS MAX.
3) JEDEC REFERENCE IS xxx.
4) DRAWING IS NOT TO SCALE.
RECOMMENDED LAND PATTERN
MPM3632S Rev. 1.03
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17
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
CARRIER INFORMATION
Part Number
Package
Description
Quantity/
Reel
Quantity/
Tube
Quantity/
Tray
Reel
Diameter
Carrier
Tape
Width
Carrier
Tape
Pitch
MPM3632SGPQZ
EC LGA
(3mmx3mmx1.45mm)
2500
N/A
N/A
13in.
12mm
8mm
MPM3632S Rev. 1.03
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18
MPM3632S – SYNCHRONOUS STEP-DOWN MINI-MODULE CONVERTER
REVISION HISTORY
Revision #
1.03
Revision
Date
11/27/2020
Description
Pages Updated
Deleted tray packaging.
2, 18
Notice: The information in this document is subject to change without notice. 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.
MPM3632S Rev. 1.03
www.MonolithicPower.com
11/27/2020
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2020 MPS. All Rights Reserved.
19
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