MP20045
Low Noise, 1A
Linear Regulator
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The Future of Analog IC Technology
DESCRIPTION
The MP20045 is a low-dropout linear regulator
supplies up to 1A current with 140mV dropout
voltage. The output voltage is set externally
which ranges from 1.5V to 5V by operating from
+2.5V to +5.5V input or can be preset internally
from 1.5V to 5V.
An internal PMOS pass element is used to
allow a low 110µA ground current, making the
MP20045 suitable for battery-power devices.
Other features include low-power shutdown,
short-circuit and thermal protection. The
MP20045 is available in 8-pin QFN (3mm x
3mm) and SOIC8E packages.
FEATURES
• Up to 1A Output Current
• Low 140mV Dropout at 1A
• Low 110µA Ground Current
• Fixed Output Versions Ranging from 1.5V to
5V and Adjustable Versions
• Open Drain Power-Good Status Output
• 13µVRMS Low Noise Output
• 56dB PSRR at 1kHz
• Current Limiting and Thermal Protection
• 3mm×3mm QFN8 and SOIC8E Packages
APPLICATIONS
• Notebook Computers
• Cordless Telephones
• Cellular Phones
• Modems
• Hand-Held Instruments
• PDA and Palmtop Computers
“MPS” and “The Future of Analog IC Technology” are Registered Trademarks of
Monolithic Power Systems, Inc.
TYPICAL APPLICATION
MP20045
COUT
2.2
VOUTVIN
EN
FB
R3
100k
CIN
PG
MP20045
R1
R2 C
OUT
2.2
C3(Optional)
0.1nF
VOUTVIN
EN
FB
R3
100k
C
IN
PG
1
OUT
2
V = (1+ )Volts
R
1.5 R
×
Fixed Version Adjustable Version
MP20045 – LOWER NOISE, 1A LINEAR REGULATOR
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ORDERING INFORMATION
Part Number* Output Voltage Package Top Marking Free Air Temperature (TA)
MP20045DQ** Adjustable QFN8 (3mm x 3mm) 8K
MP20045DQ-15** 1.5V QFN8 (3mm x 3mm) 2V
MP20045DQ-18** 1.8V QFN8 (3mm x 3mm) 3V
MP20045DQ-25** 2.5V QFN8 (3mm x 3mm) 9Z
MP20045DQ-33** 3.3V QFN8 (3mm x 3mm) 2S
MP20045DN** Adjustable SOIC8E M20045DN
MP20045DN-15** 1.5V SOIC8E 20045-15
MP20045DN-18** 1.8V SOIC8E 20045-18
MP20045DN-25** 2.5V SOIC8E 20045-25
MP20045DN-33** 3.3V SOIC8E 20045-33
-40°C to +85°C
* For fixed output voltage versions between 1.5V and 5V, add suffix –XX (e.g. MP20045DQ-33, MP20045DN-33
are the 3.3V fixed output). Contact factory for availability.
** For Tape & Reel, add suffix –Z (e.g. MP20045DQ–Z, MP20045DN–Z);
For RoHS compliant packaging, add suffix –LF (e.g. MP20045DQ–LF–Z, MP20045DN–LF–Z).
PACKAGE REFERENCE
TOP VIEW
VIN
VIN
VOUT
VOUT
1
2
3
4
EN
PG
GND
FB
8
7
6
5
VOUT
VOUT
FB
GND
VIN
VIN
EN
PG
1
2
3
4
8
7
6
5
TOP VIEW
EXPOSED PAD
ON BACKSIDE
CONNECT TO GND
QFN8 (3mm x 3mm) SOIC8E
MP20045 – LOWER NOISE, 1A LINEAR REGULATOR
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ABSOLUTE MAXIMUM RATINGS (1)
VIN, EN, PG, FB to GND ................-0.3V to +6V
OUT to GND .........................-0.5V to VIN + 0.5V
Continuous Power Dissipation (TA=+25°C) (2)
QFN8 (3x3) ......................................................2.0W
SOIC8E ............................................................2.0W
Free Air Temperature (TA).............. -40°C to 85°C
Storage Temperature Range ..... -65°C to 150°C
Lead Temperature (Soldering, 10sec)...........260°C
ESD Susceptibility
HBM (Human Body Mode)........................... 2kV
MM (Machine Mode).................................. 200V
Recommended Operating Conditions (3)
Supply Input Voltage.......................2.5V to 5.5V
Enable Input Voltage .........................0V to 5.5V
Operating Junct. Temp (TJ)...... -40°C to +125°C
Thermal Resistance (4) θJA θJC
QFN8 (3x3) .............................50 ...... 12 ... °C/W
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-to-
ambient thermal resistance JA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD(MAX)=(TJ(MAX)-
TA)/ JA. 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.
MP20045 – LOWER NOISE, 1A LINEAR REGULATOR
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ELECTRICAL CHARACTERISTICS
VIN=VOUT+0.5V or VIN=2.5V, EN=VIN, Typical values are at TA=+25°C, unless otherwise specified
Parameter Condition Min Typ Max Units
Input Voltage 2.5 5.5 V
Input Under voltage Lockout VIN rising 2.0 2.3 V
Hysteresis of UVLO 160 mV
FB Accuracy Adjustable IOUT=1mA -2.5 2.5
1.5V IOUT=1mA, 2.5V<VIN<5.5V -2.5 2.5
1.8V IOUT=1mA, 2.5V<VIN<5.5V -2.5 2.5
2.5V IOUT=1mA, 3V<VIN<5.5V -2.5 2.5
Output Voltage
Accuracy
3.3V IOUT=1mA, 3.8V<VIN<5.5V -2.5 2.5
%
Maximum Output Current Continuous, VIN>=3V 1 A
Short-Circuit Current Limit VOUT=0, VIN>=3V 1.6 A
In-Regulation Current Limit VOUT within 4% of normal output
voltage VIN=5.5V 1.4 2.2 3.0 A
Ground Current IOUT=100µA 110 µA
Dropout Voltage(5) I
OUT=1A 140 280 mV
Line Regulation(6) V
IN from VOUT+0.5V to 5.5V, IOUT=5mA -0.15 0.15 %/V
Load Regulation(7) I
OUT from 1mA to 1A -0.3 %
Output Voltage Noise
VIN=3.3V, VOUT=2.8V, COUT=2.2µF,
IOUT=100mA, f ranges from 10Hz to
100kHz
13 µVRMS
PSRR At 1kHz, IOUT=250mA 56 dB
Shutdown Supply Current VIN=+5.5V 5 16 µA
EN Logic High 1.5
EN PIN Threshold EN Logic Low 0.4 V
EN pin PULL-UP resistor 550k 1.1M
Thermal Shutdown Temperature Typical thermal hysteresis =20°C 150 °C
Minimum input voltage IOUT(PG)=300µA 1.1 1.3 V
Trip threshold voltage MP20045
MP20045-15
MP20045-18
MP20045-25
80 86
VOUT decreasing
MP20045-33 77 83
%VOUT
Hysteresis voltage Measured at VOUT 6 %VOUT
Output low voltage IOUT(PG)=1mA 0.15 0.4 V
PG
Leakage current V(PG)=5.5V 1 µA
Notes:
5) Dropout Voltage is defined as the input to output differential when the output voltage drops 100mV below its nominal value.
6) Line Regulation=
()
IN(MAX) IN(MIN)
OUT V OUT V
IN(MIN) OUT(NOM)
IN MAX
VV
100(% / V)
VV V
⎡⎤ ⎡⎤
⎣⎦ ⎣⎦
−
×
⎡⎤
−×
⎣⎦
7) Load Regulation=
()
OUT(MAX) OUT ( MIN)
OUTI OUTI
OUT NOM
VV
100(%)
V
⎡⎤ ⎡⎤
⎣⎦ ⎣⎦
−
×
MP20045 – LOWER NOISE, 1A LINEAR REGULATOR
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PIN DESCRIPTION
QFN8 (3X3)
Pin #
SOIC8E
Pin # Name Description
1, 2 7, 8 VIN
Regulator Input. Supply voltage ranges from +2.5V to 5.5V. Bypass with
2.2µF capacitor. These pins must be externally connected for proper
operation even if they are internally connected.
3, 4 1, 2 VOUT Regulator output. Bypass with a 2.2µF low-ESR capacitor to GND.
Connect all the pin together externally.
5 3 FB
Feedback Input.
For the adjustable output version, connect FB to the center point of the
external resistor divider. The feedback threshold voltage is 1.5V.
For the fixed output version, connect FB to the output directly.
6 4
GND
Expose
d pad
Ground. Connect exposed pad to GND plane for optimal thermal
performance.
7 5 PG Open-drain power-good (PG) output.
8 6 EN
Positive polarity enable (EN) input. Regulator Enable Control Input. Drive
EN above 1.5V to turn on the MP20045. Drive EN below 0.4V to turn it off.
Do not float the EN pin.
MP20045 – LOWER NOISE, 1A LINEAR REGULATOR
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TYPICAL PERFORMANCE CHARACTERISTICS
VIN=3.3V, VOUT=2.8V, CIN=COUT=2.2µF, TA=25°C, unless otherwise noted
Quiescent Current
vs. Temperature
0
20
40
60
80
100
120
-40 -20 0 20 40 60 80 100
Quiescent Current
vs. Input Voltage
0
20
40
60
80
100
120
3 3.5 4 4.5 5 5.5
QUIESCENT CURRENT(uA)
Dropout Voltage
vs. Temperature
0
20
40
60
80
100
120
140
160
180
-40-20 0 20406080100
DR OPOUT V OL T A G E (mV )
I
OUT
=1A
Dropout Voltage
vs. Output Current
0
20
40
60
80
100
120
140
160
0 200 400 600 800 1000
EN threshold
vs. Input Voltage
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
3 3.5 4 4.5 5 5.5
INPUT VOLTAGE(V)
INPUT VOLTAGE(V)
V
EN
(V)
EN high threshold
EN low threshold
EN threshold
vs. Temperature
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
-40 -20 0 20 40 60 80 100
V
EN
(V)
EN high threshold
EN low threshold
Current Limit
vs. Temperature
0
0.5
1
1.5
2
2.5
-40 -20 0 20 40 60 80 100
CURRENT LIMIT(A)
INPUT VOLTAGE (V)
Current Limit
vs. Input Voltage
0
0.5
1
1.5
2
2.5
3 3.5 4 4.5 5 5.5
CURRENT LIMIT(A)
INPUT VOLTAGE (V)
Line Regulation
-0.3
-0.2
-0.1
0.0
0.1
0.2
0.3
3.0 3.5 4.0 4.5 5.0 5.5
OUTPUT VOLTAGE ACCURACY(%)
I
OUT
=0A
I
OUT
=0.5A
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN=3.3V, VOUT=2.8V, CIN=COUT=2.2µF, TA=25°C, unless otherwise noted
Load Regulation
-0.06
-0.04
-0.02
0.00
0.02
0.04
0.06
0 200 400 600 800 1000
OUTPUT CURRENT (mA)
Output Voltage Accuracy
vs. Temperature
I
OUT
=250mA,
-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
-40 -20 0 20 40 60 80 100 10 10
3
10
5
FREQUENCY (Hz)
PSRR (dB)
Region of Stable C
OUT
ESR
vs. Output Current
0.1
1
10
100
0 200 400 600 800 1000
OUTPUT CURRENT (mA)
Stable Range
Unstable Range
102104106
I
OUT
=1A
0
10
20
30
40
50
60
70
80
90
100
PSRR Vs. Frequency
I
OUT
=800mA,
f ranges from 10Hz to 1MHz
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN=3.3V, VOUT=2.8V, CIN=COUT=2.2µF, TA=25°C, unless otherwise noted
400us/div
100us/div
Line Transient
VIN=3.3V to 4.3V, IOUT=100mA,
with Resistor Load
Line Transient
VIN=3.3V to 4.3V, IOUT=1A,
with Resistor Load
Load Transient
IOUT=50mA to 1A,
with Resistor Load
40us/div
4us/div 400us/div
400ms/div
Over Current Protection
Entry
V
IN
1V/div
I
OUT
500mA/div
I
OUT
500mA/div
V
OUT
1V/div
V
EN
5V/div
I
OUT
500mA/div
V
OUT
1V/div
V
OUT
(AC)
10mV/div
V
OUT
(AC)
10mV/div
V
OUT
(AC)
50mV/div
V
IN
1V/div
V
EN
5V/div
V
OUT
2V/div
V
IN
2V/div
I
OUT
500mA/div
I
OUT
500mA/div
V
OUT
2V/div
V
IN
2V/div
I
OUT
500mA/div
V
OUT
2V/div
V
IN
2V/div
Input Power Start Up
IOUT=1A, with Resistor Load
EN Start Up
IOUT=1A, with Resistor Load
EN Shutdown
IOUT=1A, with Resistor Load
Input Power Shutdown
IOUT=1A, with Resistor Load
2ms/div 100ms/div
V
OUT
500mV/div
PG
1V/div
40us/div
Power Good Status
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TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN=3.3V, VOUT=2.8V, CIN=COUT=2.2µF, TA=25°C, unless otherwise noted
I
OUT
500mA/div
V
OUT
2V/div
V
IN
2V/div
I
OUT
500mA/div
V
OUT
2V/div
V
IN
2V/div
Over Current Protection
Steady State
Over Current Protection
Recovery
20ms/div 40ms/div
I
OUT
500mA/div
Current Limit
4ms/div
No Load No Load
MP20045 – LOWER NOISE, 1A LINEAR REGULATOR
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BLOCK DIAGRA
Figure 1—Block Diagram of Super Low Dropout Regulation
OPERATION
The MP20045 is a low-dropout linear regulator
supplies up to 1A current. It is intended for use
in devices that require very low voltage, low
quiescent, low noise and high PSRR such as
wireless LAN, battery powered equipment and
hand-held equipment.
The MP20045 uses an internal PMOS as the
pass element and features internal thermal
shutdown and internal current limit circuit.
Dropout Voltage
Dropout voltage is the minimum input to output
differential voltage required for the regulator to
maintain an output voltage within 100mV of its
nominal value. Because the PMOS pass
element behaves as a low-value resistor, the
dropout voltage of MP20045 is very low.
Shutdown
The MP20045 can be switched ON or OFF by a
logic input at the EN pin. A high voltage at this
pin will turn the device on. When the EN pin is
low, the regulator output is off. The EN pin
should be tied to VIN to keep the regulator
output always on if the application does not
require the shutdown feature. Do not float the
EN pin.
Current Limit
The MP20045 includes a current limit structures
which monitor and control PMOS’s gate voltage
limiting the guaranteed maximum output current
to 1.2A.
Thermal Protection
Thermal protection turns off the PMOS when
the junction temperature exceeds +150ºC,
allowing the IC to cool. When the IC’s junction
temperature drops by 20ºC, the PMOS will be
turned on again. Thermal protection limits total
power dissipation in the MP20045. For reliable
operation, junction temperature should be
limited to 125 ºC maximum.
Load-Transient Considerations
The output response of load-transient consists
of a DC shift and transient response. Because
of the excellent load regulation of MP20045, the
DC shift is very small. The output voltage
transient depends on the output capacitor’s
value and the ESR. Increasing the capacitance
and decreasing the ESR will improve the
transient response.
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APPLICATION INFORMATION
Setting the Output Voltage
The output voltage of MP20045 can be set
externally which ranges from 1.5V to 5V by
operating from +2.5V to +5.5V input or preset
internally at 1.5V, 1.8V, 2.5V, 3.3V, 5V. For the
adjustable version, the output voltage is 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:
2R1R
2R
VV OUTFB +
=
Where VFB is the feedback threshold voltage
(VFB = 1.5V), and VOUT is the output voltage.
Thus the output voltage is:
R2
R2R1
1.5VOUT
+
×=
R2 can be as high as 100k, but a typical value
is 10k. Using that value, R1 is determined by:
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛−
×=
FB
FBOUT
V
VV
2R1R
For example, for a 2.8V output voltage, R2 is
10k, and R1 is 8.66k. You can select a
standard 8.66k (±1%) resistor for R1.
Power Dissipation
The power dissipation for any package depends
on the thermal resistance of the case and circuit
board, the temperature difference between the
junction and ambient air, and the rate of air flow.
The power dissipation across the device can be
represented by the equation:
()
OUTOUTIN IVVP ×−=
The allowable power dissipation can be
calculated using the following equation:
()
JAAmbientJunction(MAX) TTP θ−= /
Where (TJunction T
Ambient) is the temperature
difference between the junction and the
surrounding environment, JA is the thermal
resistance from the junction to the ambient
environment. Connecting the GND pin of
MP20045 to ground using a large pad or
ground plane helps to channel heat away.
Output Capacitor Selection
The MP20045 is designed specifically to work
with very low ESR ceramic output capacitor in
space-saving and performance consideration. A
2.2µF ceramic capacitor with ESR lower than
0.9 is suitable for the MP20045 application
circuit. Output capacitor of larger values will
help to improve load transient response and
reduce noise with the drawback of increased
size.
0.1
1
10
100
0 100 200 300 400 500 600 700 800 900 1000
OUTPUT CURRENT(mA)
C
OUT
ESR(Ω)
Figure 2—Relationship between ESR and
LDO Stability
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PACKAGE INFORMATION
SOIC8E
SEE DETAIL "A"
0.0075(0.19)
0.0098(0.25)
0.050(1.27)
BSC
0.013(0.33)
0.020(0.51)
SEATING PLANE
0.000(0.00)
0.006(0.15)
0.051(1.30)
0.067(1.70)
TOP VIEW
FRONT VIEW
SIDE VIEW
BOTTOM VIEW
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.
0.089(2.26)
0.101(2.56)
0.124(3.15)
0.136(3.45)
RECOMMENDED LAND PATTERN
0.213(5.40)
0.063(1.60)
0.050(1.27)
0.024(0.61)
0.103(2.62)
0.138(3.51)
0.150(3.80)
0.157(4.00)
PIN 1 ID
0.189(4.80)
0.197(5.00)
0.228(5.80)
0.244(6.20)
14
85
0.016(0.41)
0.050(1.27)
0o-8o
DETAIL "A"
0.010(0.25)
0.020(0.50) x 45o
0.010(0.25) BSC
GAUGE PLANE
MP20045 – LOWER NOISE, 1A 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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QFN8 (3mm×3mm)
SIDE VIEW
TOP VIEW
1
8
54
BOTTOM VIEW
2.90
3.10
1.45
1.75
2.90
3.10
2.25
2.55
0.65
BSC
0.20
0.30
0.80
1.00
0.00
0.05
0.20 REF
PIN 1 ID
MARKING
1.70
0.65
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 VEEC-2.
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
0.30x45º TYP.
DETAIL A
0.30
0.50
PIN 1 ID
INDEX AREA
