MP2040
Fast Transient Response, 3A Dual Supply
Very Low Dropout Linear Regulator
MP2040 Rev.1.0 www.MonolithicPower.com 1
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The Future of Analog IC Technology
DESCRIPTION
The MP2040 is a very low dropout, dual supply
linear regulator. The use of two supplies allows
the BIAS to control an NMOS device. The
NMOS device supplies power to the load via
the IN. In this way the input supply can be just
above the desired output, yet still provide very
good regulation performance due to the higher
bias supply. The BIAS operates from a 3.3V to
5.5V input and regulates the output voltage to
as low as 0.9V, and as high as 3.3V.
The MP2040 can supply up to 3A of load
current with a typical dropout voltage of 150mV.
The BIAS runs the internal reference and drive
circuitry, while the output current comes directly
from the IN for high efficiency regulation.
Other features of MP2040 include thermal
overload and current limit protection, power
good indicator, stability with ultra low ESR
ceramic capacitors as low as 1uF, and fast
transient response. The MP2040 is available in
10-pin QFN (3mm x 3mm), and in QFN (5mm x
5mm) packages.
FEATURES
• Wide 1.1V to 5V Input Voltage Range
• Stable with Very Small Ceramic Capacitors
• 150mV Dropout at 3A Output
• 2% Accurate Output Voltage
• Adjustable Output Range of 0.9V to 3.3V
• Low Noise: 80µVRMS (10Hz to 100kHz)
• Very fast transient response
• PSRR
o 40dB at 100kHz
• Better Than 0.001%/mA Load Regulation
• Stable With Low-ESR Output Capacitors
• Internal Thermal Protection
• Current Limit Protection
• 0.1µA Typical Quiescent Current at
Shutdown
• Power Good Indicator
APPLICATIONS
• Industrial Process & Control Equipment
• Telecom Equipment
• PAID Storage
• DSP/ASIC/µC Post Regulation for Switching
Power Supplies
“MPS” and “The Future of Analog IC Technology” are Registered Trademarks of
Monolithic Power Systems, Inc.
TYPICAL APPLICATION
C6
10nF
U1
IN OUT
OUT
FB
EN
BP
IN
BIAS
PG
GND
MP2040
5
3
1
8
9
6
10
7
2
4
VIN
BIAS
PGOOD
GND
C8
1nF
EN
VOUT
1.2V/3A
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
MP2040 Rev.1.0 www.MonolithicPower.com 2
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ORDERING INFORMATION
Part Number Package Top Marking Free Air Tem perature (TA)
MP2040DQ* 3x3 QFN10 7D -40°C to +85°C
MP2040DU** 5x5 QFN32 MP2040DU -40°C to +85°C
* For Tape & Reel, add suffix –Z (e.g. MP2040DQ–Z).
For RoHS compliant packaging, add suffix –LF (e.g. MP2040DQ–LF–Z)
** For Tape & Reel, add suffix –Z (e.g. MP2040DU–Z).
For RoHS compliant packaging, add suffix –LF (e.g. MP2040DU–LF–Z)
PACKAGE REFERENCE
TOP VIEW
VIN
VIN
BIAS
PGOOD
GND
1
2
3
4
5
VOUT
VOUT
FB
EN
BYPASS
10
9
8
7
6
EXPOSED PAD
ON BACKSIDE
TOP VIEW
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
N/C
VIN
VIN
VIN
VIN
BIAS
PGOOD
GND
N/C
VOUT
VOUT
VOUT
VOUT
FB
EN
BYPASS
N/C N/C N/C N/C N/C N/C N/C N/C
N/C N/C N/C N/C N/C N/C N/C N/C
910111213141516
32 31 30 29 28 27 26 25
EXPOSED PAD
ON BACKSIDE
3x3 QFN10 5x5 QFN32
ABSOLUTE MAXIMUM RATINGS (1)
VBIAS, VIN to GND.............................-0.3V to +6V
FB, EN, to GND ................................-0.3V to 6V
VOUT................................-0.3V to VIN + 0.3 or 6V
PGOOD ......................-0.3V to VBIAS + 0.3 or 6V
BYPASS ......................-0.3V to VBIAS +0.3 or 6V
Continuous Power Dissipation (TA = +25°C) (2)
QFN10 3X3................................................ 2.5W
QFN32 5X5.............................................. 3.47W
Junction Temperature...............................150°C
Lead Temperature ....................................260°C
Storage Temperature .............. -65°C to +150°C
Recommended Operating Conditions (3)
Input Voltage VIN .............................1.1V to 5.5V
Input Voltage VBIAS ..........................3.3V to 5.5V
Output Voltage................................0.9V to 3.3V
Load Current...............................3.0A Maximum
Operating Junct. Temp (TJ)...... -40°C to +125°C
Thermal Resistance (4) θJA θJC
QFN10 3X3… ......................... 50……12 °C/W
QFN32 5X5… ......................... 36….…8 °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-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 powe
r
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.
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
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ELECTRICAL CHARACTERISTICS
VIN = 1.5V, VBIAS = 3.6V, VOUT = 1.2V, COUT = 1µF, CIN = 0.1µF, TA = +25°C, unless otherwise noted.
Parameter Symbol Condition Min Typ Max Units
VIN Operating Voltage 1.1 5.5 V
VBIAS Operating Voltage IOUT = 2A 3.3 5.5 V
VBIAS Operating Current 3.5 mA
0.5 0.51 0.52
FB Regulation Voltage -40°C ≤ TA ≤ +85°C 0.495 0.51 0.525 V
Dropout Voltage IOUT = 3A, VBIAS = 3.6V 150 mV
VIN Line Regulation
IOUT = 1mA,
VIN = 1.5 to 5V
VBIAS = 5V VOUT = 1.2V
1 mV
VBIAS Line Regulation
IOUT = 1mA,
VBIAS = 3.6V to 5.5V VOUT = 1.2V
VIN = 1.5V
2 mV
Load Regulation IOUT = 1mA to 1A 0.001 %/mA
PSRR (VIN)
VIN > VOUT + 0.5V, COUT = 4.7µF,
VIN(AC) = 100mV, f = 100kHz
VB=5V
40 dB
Power Good Threshold 440 mV
Power Good Delay 80 µs
Current Limit (5) 3.6 A
Soft Start BYPASS=open 280 µs
Power Good Voltage Isink=230µA 0.39 V
EN Input High Voltage 1.5 V
EN Input Low Voltage 0.8 V
EN Input Bias Current VEN = 1.2V –1 +1 µA
Thermal Protection 135 °C
Thermal Protection Hysteresis 15 °C
Notes:
5) Guaranteed by Designer.
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
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PIN FUNCTIONS
QFN3X3 10pins
Pin # Name Description
9, 10 VOUT Regulator Output. OUT is the output of the linear regulator, By pass OUT to GND with a
4.7µF or greater capacitor.
3 BIAS Bias Voltage. Bypass to ground with a 1µF or greater capacitor, VB>=VIN.
8 FB
Feedback Input. Connect a resistive voltage divider from OUT to FB to set the output
voltage. OUT feedback threshold is 0.51V.
7 EN
Enable Input. Drive EN high to turn on the MP2040, drive EN low to turn it off. For
automatic startup, connect EN to IN.
5 GND Ground, exposed pad.
1, 2 VIN Power Source Input. IN supplies power to the load at the output (through the power
transistor). Bypass IN to GND with a 1µF or greater capacitor.
4 PGOOD Open drain output. High indicated VOUT> 90% final value.
6 BYPASS Connect a 1nF to this pin. Do not load this pin resistively.
QFN5x5 32pins
Pin # Name Description
20, 21,22,
23 VOUT Regulator Output. OUT is the output of the linear regulator, By pass OUT to GND with a
4.7µF or greater capacitor.
6 BIAS Bias Voltage. Bypass to ground with a 1µF or greater capacitor, VB>=VIN.
19 FB
Feedback Input. Connect a resistive voltage divider from OUT to FB to set the output
voltage. OUT feedback threshold is 0.51V.
18 EN
Enable Input. Drive EN high to turn on the MP2040, drive EN low to turn it off. For
automatic startup, connect EN to IN.
8 GND Ground, exposed pad.
2, 3, 4, 5 VIN Power Source Input. IN supplies power to the load at the output (through the power
transistor). Bypass IN to GND with a 1µF or greater capacitor.
7 PGOOD Open drain output. High indicated VOUT> 90% final value.
17 BYPASS Connect a 1nF to this pin. Do not load this pin resistively.
1, 9, 10,
11, 12,
13, 14,
15, 16,
24, 25,
26, 27,
28, 29,
30, 31, 32
NC These are no connection pins.
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
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TYPICAL PERFORMANCE CHARACTERISTICS
C1=22µF, C2=0.1µF, C3=1.0µF, C4=4.7µF, C6=22nF, VB=5V, TA=25ºC, unless otherw ise noted
.
Load Regulation
Line Regulation
Load Regulation
Line Regulation
0
20
40
60
80
100
120
140
160
0.0 0.8 1.6 2.4 3.2 4.0
LOAD CURRENT ( A )
VOLTAGE DROPPED (mV )
0
1.190
1.194
1.198
1.202
1.206
1.210
1.5 1.9 2.3 2.7 3.1 3.5
INPUT VOLTAGE ( V )
OUTPUT VOLTAGE ( V )
Voltage Dropout
V
OUT
=1.2V
Line Regulation
1.190
1.194
1.198
1.202
1.206
1.210
0.0 0.6 1.2 1.8 2.4 3.0
LOAD CURRENT ( A )
OUTPUT VOLTAGE (V)
V
IN
=1.8V
V
IN
=1.5V
I
IN
=1.0A
I
IN
=0.6A
Load Regulation
-20
-10
0
10
20
30
40
50
60
70
80
0.1 1 10 100 1000 10000
FREQUENCY (kHz )
PSRR ( dB )
PSRR vs. Frequency
V
IN
=1.5V,V
OUT
=1.2V
1.790
1.796
1.802
1.808
1.814
1.820
2.0 2.3 2.6 2.9 3.2 3.5
INPUT VOLTAGE ( V )
OUTPUT VOLTAGE ( V )
OUTPUT VOLTAGE ( V )
I
IN
=1.0A
I
IN
=0.6A
1.800
1.804
1.808
1.812
1.816
1.820
0.0 0.6 1.2 1.8 2.4 3.0
LOAD CURRENT ( A )
INPUT VOLTAGE ( V ) LOAD CURRENT ( A )
V
IN
=2.5V
V
IN
=1.8V
OUTPUT VOLTAGE ( V )OUTPUT VOLTAGE ( V )
20
30
40
50
60
70
80
0.5 1.0 1.5 2.0 2.5 3.0
P
D
(W)
CASE TEMPERATURE (
O
C )
MP2040DU Case
Temperature vs. PD
V
B
=5V,V
OUT
=1.2V
2.48
2.49
2.50
2.51
2.52
2.53
2.5 2.8 3.1 3.4 3.7 4.0
2.45
2.47
2.49
2.51
2.53
2.55
0.0 0.6 1.2 1.8 2.4 3.0
I
IN
=0.6A
I
IN
=1.0A
V
IN
=3.5V
V
IN
=2.8V V
IN
=3.3V
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
C1=22µF, C2=0.1µF, C3=1.0µF, C4=4.7µF, C6=22nF, VB=5V, TA=25ºC, unless otherw ise noted
V
DROPOUT
vs. Temperature
VO=1.2V, IO=1A
25
28
31
34
37
40
-45 -25 -5 15 35 55 75 95
VDROPOUT(mV)
VOUT(V)
0.504
0.506
0.508
0.51
0.512
0.514
-40 -10 20 50 80 110
VBF VOLTAGE (V)
V
BF
vs. Temperature
VIN=1.5V, VB=3.6V
V
OUT
vs. Temperature
VIN=1.5V, VO=1.5V, IO=1mA
1.18
1.19
1.20
1.21
1.22
1.23
-45 -25 -5 15 35 55 75 95
Load Transient
VIN=1.9V, VO=1.2V, IO=0 to 3A Enable Turn ON
VIN=1.6V, VO=1.2V,
VEN=0V to 3V, IO=3A
Enable Turn Off
VIN=1.6V, VO=1.2V,
VEN=3V to 0V, IO=3A
Short Circuit
VIN=2.1V, VO=1.2V
Short Circuit Recovery
VIN=2.1V, VO=1.2V Thermal Prote ct i on
VIN=3.8V, VO=2.5V, IO=3.6A
V
O
20mV/div.
V
O
1V/div.
V
PG
5V/div.
V
EN
2V/div.
I
O
2A/div.
V
O
2V/div.
I
O
5A/div.
V
O
2V/div.
I
O
5A/div.
I
O
5A/div.
V
O
1V/div.
V
PG
5V/div.
V
EN
2V/div.
I
O
5A/div.
V
O
2V/div.
V
PG
5V/div.
V
IN
2V/div.
I
O
2A/div.
1ms 20ms
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
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TYPICAL PERFORMANCE CHARACTERISTICS (CONTINUED)
C1=22µF, C2=0.1µF, C3=1.0µF, C4=4.7µF, C6=22nF, VB=5V, TA=25ºC, unless otherw ise noted
Line Transient
V
IN
=1.5V to 4.5V, V
O
=1.2V, I
O
=0.4A
VO
1V/div.
VPG
5V/div.
VIN
1V/div.
IO
2A/div.
VO
1V/div.
VB
5V/div.
VIN
1V/div.
IO
2A/div.
VO
20mV/div.
VIN
2V/div.
4ms 4ms 4ms
Power Ramp Up
V
IN
=1.5V, V
O
=1.2V, I
O
=3A
with Resistor load
Power Ramp Down
V
IN
=1.5V, V
O
=1.2V, I
O
=3A
with Resistor load
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
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BLOCK DIAGRAM
BYPASS
BIAS
EN
GND
PGOOD
O
FB
VOUT
VIN
+
--
+
--
0.5V
0.45V
REFERENCE
SOFT
START
GATE
TURNS OFF
THE GATE
--
+
Figure 1—Block Diagram of Low Dropout Regulator
OPERATION
MP2040 Theory of Operation
The MP2040 linear dropout regulator provides
adjustable output voltages from 0.9V to 3.3V at
currents up to 3A. This LDO is protected against
short circuits, and it has thermal shut down
protection with 15oC hystheresis.
Utilizing Two Power Supplies
In order to maximize the efficiency MP2040 uses
two power supplies. One power supply is
connected to the BIAS pin and it is used to power
up the internal circuitries including band gap
reference and the rest of control circuitries. The
other power supply is connected to the VIN pins
which are the drain of pass device. This power
supply can be set close to output voltage of LDO.
The output pins are the source of the pass
device. The smaller voltage drop across the pass
device translates to the smaller power loss in
pass device. Thus, the part operates with higher
efficiency.
Internal Current Limit
The MP2040 has an internal current limit set at
almost 3.8A. Internal current limit is very well
controlled over process variations and ambient
temperature.
Enable
The enable (EN) pin is active high. The enable
pin has a built-in hystheresis. If this pin is held
below 0.8V then part shuts down and draws less
than 1uA from VBIAS supply.
If not used then connect this pin to VBIAS.
Under Voltage Lockout
The Bias voltage is monitored by a circuit that
prevents the LDO start up when the bias voltage
is below 2.35V. This circuitry has an approximate
hystheresis of 90mV.
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Soft Start
MP2040 incorporates internal soft start function.
This internal function reduces the start up current
surge into the output capacitor. This allows the
gradual built up of output voltage to its final set
value. The internal soft start cap is held to ground
if there is a fault condition. The fault conditions
are UVLO, Thermal shut down, and disable. The
internal soft start time is almost 280µ
Power Good
The Power Good pin is an open drain output and
can be connected to Bias voltage via a pull up
resistor. Open drain transistor turns off and PG
pin voltage value becomes VBIAS when VFB
exceeds 450mV. Also PG pin can sink at least
230µA while being low.
Setting the Output Voltage
The MP2040 has an adjustable output voltage,
set by 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 x R2/ (R1+R2)
Where VFB is the feedback threshold voltage
(VFB=0.5V), and VOUT is the output voltage. R1
connects between VOUT and VFB, and R2 connects
between VFB and ground.
Thus the output voltage is:
VOUT = 0.5 x (R1+R2)/R2
R2 can be as high as 100kΩ, but a typical value
is 10kΩ. Using that value, R1 is determined by:
R1=R2 x (VOUT-VFB)/VFB
For example, for a 1.8V output voltage, R2 is
10kΩ, and R1 is 26kΩ. You can select 26kΩ (1%)
resistor for R1.
Power Dissipation
Most of the power dissipation is due to power
dissipation in PASS device. For example,
assume VBIAS=5.0V, VIN=2.0V, VOUT=1.8V, and
IOUT=3A:
PD (PASS) = (VIN-VOUT) x IOUT
PD (PASS) = (2.0V-1.8V) x 3A=0.6W
PBIAS = VBIAS x IGND= 5V x (220µA) = 1.25mW.
This is negligible compared to PD (PASS) =0.6W
For QFN 3X3 θJA is 50oC/W.
0.6W power is dissipated when 3A output current
goes through PASS device with VIN=2.0V, and
VOUT=1.8V.
This gives a rise in die temperature for 0.6 x
50oC/W=30oCThis is a safe operating point
assuming a junction temperature of 135oC at an
85oC ambient temperature.
A heat sink needs to be utilized for a better
temperature performance.
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APPLICATION INFORMATION
PG
The power good pin is an open drain output a
pull up resistor (100kΩ recommended). The pull
up resistor can be tied to a supply within the
voltage range of the pin (0 to 5.5V). For example,
the pull up resistor can be tied to the input
voltage that is monitored by an IC powered from
this input voltage. If the output voltage is 10%
below its regulation point, the PG pin becomes
low.
Bypass Capacitors
For lower noise, the reference voltage can be
bypassed by an external capacitor. A low ESR
capacitor, such as the ceramic type, will provide
the best performance.
It also can function as an external soft start, the
soft start time;
Tss=1000 x CBP
Performance Transient Response
For a 3A transient response, suggests increasing
the input capacitance should be increased to
22µF or higher to get better performance. This
will also avoid glitches on the PG pin due to
excessive undershoot. Also increase the input
voltage 0.4V above the VOUT, to improve the load
transient response.
Maximum Output Voltage and Load Current
If the VOUT is set to 3.3V then the maximum
output current will be decreased to 2.5A. The
maximum bias voltage limits the VOUT. VOUT must
be at least 2.5V less than VB;
VOUT=VB -2.5V
Bias Input Voltage
The bias input is designed for low drop
application. The bias pin must be at least 3.3V,
and at least 2.5V higher than the output voltage.
If the VIN supply voltage meets these
requirements, the bias pin can be tied to VIN.
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PACKAGE INFORMATION QFN10 (3mm x 3mm)
SIDE VIEW
TOP VIEW
110
65
BOTTOM VIEW
2.90
3.10 1.45
1.75
2.90
3.10 2.25
2.55
0.50
BSC
0.18
0.30
0.80
1.00
0.00
0.05
0.20 REF
PIN 1 ID
MARKING
1.70
0.50
0.25
RECOMMENDED LAND PATTERN
2.90
NOTE:
1) ALL DIMENSIONS ARE IN MILLIMETERS.
2) EXPOSED PADDLE SIZE DOES NOT INCLUDE MOLD FLASH.
3) LEAD COPLANARITY SHALL BE 0.10 MILLIMETER MAX.
4) DRAWING CONFORMS TO JEDEC MO-229, VARIATION VEED-5.
5) DRAWING IS NOT TO SCALE.
PIN 1 ID
SEE DETAIL A
2.50
0.70
PIN 1 ID OPTION B
R0.20 TYP.
PIN 1 ID OPTION A
R0.20 TYP.
DETAIL A
0.30
0.50
PIN 1 ID
INDEX AREA
MP2040 –FAST TRANSIENT RESPONSE, 3A VERY LOW DROPOUT LINEAR REGULATOR
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.
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QFN32 (5mm x 5mm)
