5V-Adjustable High-PSRR Low-Noise LDO
MD7671 Series
CMOS Voltage Regulator With ON/OFF Switch
PRODUCT DESCRIPTION
MD7671
highly
1A
FEATURES
series
are
⚫
Highly Accurate: ±2%
accurate,
low-
⚫
Low Quiescent Current: 40µA
noise, high power supply
⚫
Dropout Voltage: 160mV@3.3V/1A
rejection ratio (PSRR),
⚫
Maximum Output Current: 1A
low-dropout
voltage
⚫
Input Voltage Range: 2~6V
regulator (LDO) with high output current capability
⚫
Output Voltage Noise: 115μVrms@VOUT=3.3V
manufactured in CMOS processes. It can deliver up
⚫
High PSRR:70dB@1kHz
to 1A of current while consuming 40µA of quiescent
⚫
Temperature Stability: ±50ppm/℃
current. Internal circuitry includes a reference
⚫
ON/OFF Logic = Enable High
voltage generator, an error amplifier, driver transistor,
⚫
Power Good and Enable Functions
over-current
short-circuit
⚫
Standby Current: 10nA
protection circuit, thermal shutdown circuit and a
⚫
COUT Discharge Circuit when EN Disable is Active
phase compensation circuit. The MD7671 operates
⚫
Protections Circuits: Current Limit, Short Circuit,
protection
circuit,
by default as a fixed output voltage regulator (default
and Thermal Protections
output voltage: 5V) while usage of an external
⚫
resistor divider allows adjustable out voltages as low
Output Capacitor: Low ESR Ceramic Capacitor
Compatible
as 0.7V. Additional features include enable function,
⚫
power good flag and output noise reduction pin.
RoHS compliant “Green”/Halogen Free 8-pin
Exposed pad SOIC (ESOP8) packages, TO252-4,
SOT89-3 and SOT23-5 packages
APPLICATIONS
⚫
Smart wearer
⚫
Long-life battery-powered devices
⚫
Portable mobile devices, such as mobile
phones, cameras, and so on
⚫
Wireless communication equipment
TYPICAL APPLICATION CIRCUIT:
10k
R3
ADJ
VOUT 3.3V/1A
VIN
VOUT
EN
ADJ
GND
BP
GND
MD7671A
COUT
4.7μF
CIN
4.7μF
Enable
GND
MD7671B
R1
R1
PGOOD
390k
390k
R2
4.7μF
PGOOD
EN
VIN 3.6V - 6V
105k
CIN
VOUT
R2
Enable
VOUT 3.3V/1A
VIN
105k
VIN 3.6V - 6V
COUT
4.7μF
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
PIN CONFIGURATION (TOP VIEW)
MD7671B
MD7671A
EN
1
VIN
2
8
GND
7
PGOOD
VOUT
1
ADJ
2
GND
VOUT
3
ADJ
4
VOUT
8
VIN
7
N.C.
6
N.C.
5
EN
SOT23-5
4
GND
6
BP
GND
3
5
GND
N.C.
4
ESOP8
ESOP8
7671
1
2
3
VIN
GND
EN
SOT89-3
SOT89-3
2
MD7671
GND
3
2
7671EXX
ADJ/NC
5
7671
7671AXX
3
1
2
3
1
2
VOUT
GND
VIN
GND
VIN
1
3
2
EN VIN
VOUT
4
5
VOUT ADJ
TO252-4L
PRODUCT SELECTIONS
Type
Fixed Output
Voltage(note 1*)
ADJ
Accuracy
(note 2*)
Package
(note 3*)
MARKING
(note 4*)
MD7671A50SF4
5V
Yes
±2%
ESOP8
7671A
MD7671B50SF4
5V
Yes
±2%
ESOP8
7671B
MD7671E50QC3
5V
Yes
±2%
SOT23-5
7671
MD7671E33PA1
3.3V
No
±2%
SOT89-3
7671E33
MD7671A33PA1
3.3V
No
±2%
SOT89-3
7671A33
MD7671E50UB2
5V
Yes
±2%
TO252-4L
7671
Notes:
1* Customer can request to customize the output voltage ranged from 1.2V to 5V if desired voltage is not found in the selections.
2* Customer can request customization of accuracy requirement.
3* Customer can request customization of package choice.
4* Please pay attention to the MARKING of the product package type.
2 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
PIN DESCRIPTION
VOUT
ESOP8
(MD7671A)
3
ESOP8
(MD7671B)
1
SOT23-5
(MD7671EXX)
5
ADJ
4
2
-
GND
5,8
3
2
EN
1
5
3
VIN
2
8
1
BP
6
-
-
PGOOD
7
-
-
N.C.
-
4,6,7
-
GND
Exposed
Pad
Exposed
Pad
-
Name
Description
Regulator Output pin.
Adjustable Pin.
Output Voltage can be set by external feedback
resistors when using a resistive divider. Or,
connect ADJ to GND for VOUT = 5V, set by internal
feedback resistors.
Ground Signal
Enable Pin.
Minimum 1.6V to enable the device. Maximum
0.4V to shutdown the device.
Power Input Pin.
Must be closely decoupled to GND pin with a
4.7μF or greater ceramic capacitor.
Bypass pin.
Connect a 1μF capacitor to GND to reduce output
noise. Bypass pin can be left floating if
unnecessary.
Power Good open Drain Output
Non Connection (Used to connect GND or OPEN
state.)
Connect to GND.
ABSOLUTE MAXIMUM RATINGS
PARAMETER
Input Voltage
Output Voltage
Power Dissipation
Thermal Resistance
Operating Ambient Temperature
Storage Temperature
ESD Protection
SYMBOL
VIN
VOUT
PD
RθJB(1)
Topr
Tstg
ESD HBM
(Unless otherwise indicated: Ta=25℃)
RATINGS
UNITS
-0.3 ~ 7
V
-0.3 ~ VIN+0.3
Internally Limited
ESOP8
80
SOT23-5
180
℃/W
SOT89-3
100
TO252-4
60
-40 ~ +85
℃
-40 ~ +125
4000
V
Note: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device.
(1)
Mounted on JEDEC standard 4layer (2s2p) PCB test board
3 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
ELECTRICAL CHARACTERISTICS
Unless otherwise indicated, VIN = VOUT + 1V, CIN = 4.7µF, COUT = 4.7µF, CBYP=1µF, TJ = 25°C.
PARAMETER
Input Voltage
Output Voltage Tolerance
Continuous Output Current
SYMBOL
VIN
VOUT(S)
IOUT
15
mV
VIN=VEN=VOUT(S)+1.0V
1mA≤IOUT≤1A
10
20
mV
VIN=VEN =VOUT(S)+1.0V
ΔVOUT
IOUT=1mA
𝛥𝑇𝑎 • 𝑉𝑂𝑈𝑇(𝑠)
-40℃≤TA≤125℃
±50
Dropout Voltage*2
VDROP
Line Regulation
VOUT2
VEN=VIN, IOUT=1A, VOUT=1.8V
VEN=VIN, IOUT=1A, VOUT=3.3V
VEN=VIN, IOUT=1A, VOUT=5V
VOUT(S)+1V≤VIN=VEN≤6V
IOUT=1mA
Reference Voltage Tolerance
0.686
VADJ = VREF
Output ON
Output OFF
0.05
1.6
μA
μA
A
ppm/
℃
0.7
0.714
10
0.1
0.2
0.1
0
0.4
0.5
V
nA
V
V
V
μA
μs
30
Ω
90
10
1
0.05
70
68
47
55
%
%
ms
V
115
µVRMS
TSD
175
℃
TSD_HYS
35
℃
PGHTH
PGHYS
PGDLY
Power Supply Ripple Rejection
PSRR
Output Noise Voltage
VOUTN
Thermal Shutdown Hysteresis
UNIT
V
%
A
3
ISHUT
ILIM
Thermal Shutdown Temperature
MAX.
6
+2
mV
Shutdown Current
Output Current Limit
Current Fold Back
ADJ Pin Current
ADJ Pin Threshold
Enable Turn-On Threshold
Enable Turn-Off Threshold
Shutdown Pin Current
Shutdown Exit Delay Time
Max Output Discharge
Resistance
to GND during Shutdown
PGOOD Rise Threshold
PGOOD Hysteresis
PGOOD Delay
PGOOD Sink Capability
TYP.
300
250
240
IGND
Temperature Stability
IOUT=1mA
VIN>2.1V
VEN=VIN, no load
VEN=VIN, IOUT=100mA
VEN=0
MIN.
2
-2
1
40
390
0.01
1.4
0.4
210
160
150
Ground Current
Load Regulation
CONDITIONS
IPGOOD = 10mA
f=1kHz, IOUT=10mA
f=10kHz, IOUT=10mA
f=100kHz, IOUT=10mA
f=1MHz, IOUT=10mA
CBP = 1µF, VOUT=3.3V
f=10Hz ~100KHz
Notes:
1.
VOUT(S): Output voltage when VIN=VOUT+1V, IOUT=1 mA.
2.
VDROP=VIN1 -(VOUT(S)× 0.98)where VIN1 is the input voltage when VOUT = VOUT(S)× 0.98.
3.
ILIM: Output current when VIN=VOUT(S)+1V and VOUT = 0.95*VOUT(S).
4 / 14
dB
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
TYPICAL PERFORMANCE CHARACTERISTICS
Test Conditions: VIN=VOUT+1.0V, CIN = 4.7μF, COUT = 4.7μF, TA=25℃, unless otherwise indicated.
3.6
80
GND Current IGND(μA)
Output Voltage VOUT(V)
3.5
3.4
3.3
3.2
60
40
20
3.1
IOUT =1mA
3
-40
-20
0
20
40
60
80
100
120
0
140
-40
-20
0
Junction Temperature Ta(℃)
40
60
80
100
120
140
GND Current vs. Temperature at VOUT=3.3V
140
3.5
120
3
Output Voltage VOUT(V)
GND Current IGND(uA)
Output Voltage vs. Temperature at VOUT=3.3V
100
80
60
40
2.5
2
1.5
1
0.5
20
0
0
0
1
2
3
4
5
0
6
1
2
3
4
5
6
Input Voltage VIN(V)
Input Voltage VIN(V)
Output Voltage vs Input Voltage at VOUT=3.3V
GND Current vs. Input Voltage at VOUT=3.3V
3.36
1600
1400
3.34
1200
Output Voltage VOUT(V)
GND Current IGND(uA)
20
Input Voltage VIN(V)
1000
800
600
400
3.32
3.3
3.28
3.26
200
3.24
0
0
0.2
0.4
0.6
0.8
0
1
0.2
0.4
0.6
0.8
Output Current IOUT(A)
Output Current IOUT(A)
Output Voltage vs Output Current at VOUT=3.3V
GND Current vs Output Current at VOUT=3.3V
5 / 14
1
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
TYPICAL PERFORMANCE CHARACTERISTICS(CONTINUTED)
200
90
180
80
160
-40°
140
25°
120
85°
Ripple Rejection Rate RR(dB)
Dropout Voltage VDROP(mV)
Test Conditions: VIN=VOUT+1.0V, CIN=4.7μF, COUT= 4.7μF, TA=25℃, unless otherwise indicated.
100
80
60
40
20
0
0
0.2
0.4
0.6
0.8
70
60
50
40
30
20
VIN=4.3V DC+200mVPP AC
IOUT =10mA
10
0
0.01
1
0.1
Output Current IOUT(A)
1
10
100
1000
Ripple Frequencey f (kHz)
Dropout Voltage vs. Output Current at VOUT=3.3V
Power Supply Rejection Ratio at VOUT=3.3V
Ch1=VOUT
Ch1=VOUT
Offset=4.3V
Ch4=IOUT
Load Transient at VOUT=3.3V
(IOUT=10mA~1A~10mA)
Ch2=VIN
Line Transient at VOUT=3.3V
(IOUT=10mA)
Ch1=VOUT
Ch1=VOUT
Ch2=EN
Ch2=EN
Ch3=PGOOD
Ch3=PGOOD
Enable Startup at VOUT=3.3V
(IOUT=0mA)
Enable Shutdown at VOUT=3.3V
(IOUT=0mA)
6 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
TYPICAL PERFORMANCE CHARACTERISTICS(CONTINUTED)
Test Conditions: VIN=VOUT+1.0V, CIN=4.7μF, COUT= 4.7μF, TA=25℃, unless otherwise indicated.
Ch4=IOUT
Output Current Fold-back at VOUT=3.3V
7 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
BLOCK DIAGRAM
VIN
Reference
Buffer
BP
Error
AMP
Soft-Start
VOUT
Thermal
Shutdown
EN
Current
Limit
Enable/Shutdown
Logic
GND
ADJ
Selector
PGOOD
0.63V
0.1V
ADJ
THEORY OF OPERATION
The MD7671 is a low-dropout voltage regulator with low quiescent current, low noise and high PSRR. It can
support load current up to 1A. It incorporates current-limit and thermal protection features.
SHUTDOWN
By connecting EN pin to GND, the MD7671 can be shutdown to reduce the supply current to 0.01μA (typ.). In this
mode, the output voltage of MD7671 is equal to 0V.
CURRENT LIMIT and SHORT CIRCUIT PROTECTION
The MD7671 includes current limit protection feature, which monitors and controls the maximum output current. If
the output is overloaded or shorted to ground, this can protect the device from being damaged.
When output is
shorted to ground, current limit will be adjusted to about 25% of the rated current limit to protect the device.
THERMAL PROTECTION
The MD7671 includes a thermal protection feature that protects the IC by turning off the pass transistor when the
maximum junction temperature TJ exceed 175℃.
POWER DISSIPATION
The power dissipation across the device can be calculated as:
PD = IOUT ∗ (VIN − VOUT )
The total junction temperature is calculated as:
TJ = TA + (PD ∗ θJA)
where, TJ is the junction temperature, TA is the ambient temperature and θJA is the thermal resistance between
junction to ambient. There is a temperature rise associated with this power dissipated while operating in a given
ambient temperature. If the calculated junction temperature exceeds maximum junction temperature specification,
then the built-in thermal protection feature is triggered as described previously. To insure reliable performance, the
maximum allowable power dissipation for a given ambient temperature must be considered and it can be
calculated as follows:
PD(MAX) = (TJ(MAX) − TA )⁄θJA
8 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
where, TJ(MAX) is the maximum junction temperature, TA is the ambient temperature and θJA is the thermal
resistance between junction to ambient. In order to insure the best thermal flow, proper mounting of the IC is
required.
INPUT & OUTPUT CAPACITORS
MD7671 is optimized for use with ceramic capacitors. In order to ensure stability of the device, please place an
output ceramic capacitor of 4.7µF or bigger at the VOUT pin and GND pin as close as possible. An input capacitor of
4.7µF is recommended. X5R or X7R ceramic capacitors are recommended as they have the best temperature and
voltage characteristics. If the impedance of the power supply is high, which is caused by forgetting installing input
capacitor or installing too small value capacitor, the oscillation may occur.
When large output current switching (>500mA) are required in the application, a greater value of input/output
capacitors (≥10 µF) would be recommended to ensure the device to operate smoothly.
TYPICAL APPLICATION SCHEMATIC
10k
R3
VOUT
EN
ADJ
R1
PGOOD
GND
BP
GND
COUT
CIN
4.7μF
4.7μF
Enable
GND
MD7671A
MD7671B
R1
390k
R2
4.7μF
ADJ
VOUT 3.3V/1A
VIN
390k
PGOOD
EN
VIN 3.6V-6V
105k
CIN
VOUT
R2
Enable
VOUT 3.3V/1A
VIN
105k
VIN 3.6V-6V
COUT
4.7μF
PROGRAMMING THE OUTPUT VOLTAGE
MD7671’s internal feedback resistors set the output voltage VOUT to 5V when the ADJ pin is connected to GND.
Alternatively; the output voltage is adjustable via the external feedback resistor network R1 and R2 by calculating
the following formula:
VOUT = VREF ∗ (1 +
R1
)
R2
where, VREF is the reference voltage set internally at 0.7V nominal.
NOISE BYPASS CAPACITOR (For MD7671A)
A 1µF bypass capacitor at BP pin can reduce output voltage noise. This pin can be left floating if it is unnecessary.
POWER-GOOD FUNCTION
The power-good circuit monitors the voltage at the feedback pin to indicate the status of the output voltage. When
the output voltage falls below the PGOOD fall threshold voltage (PGLTH), the PGOOD pin open-drain output
engages and pulls the PGOOD pin close to GND. When the output voltage exceeds PGOOD rise threshold voltage
(PGHTH), the PGOOD pin becomes high impedance. By connecting a pullup resistor to external pullup supply
voltage (default for VOUT), any downstream device can receive power-good as a logic signal that can be used for
sequencing. Make sure that the external pullup supply voltage results in a valid logic signal for the receiving device.
Using a pullup resistor from10 kΩ to 100 kΩ is recommended.
LAYOUT CONSIDERATION
1. Connect the bottom-side pad to a large ground plane for good thermal conductivity and to reduce the thermal
resistance of the device.
2. The input Capacitor CIN and output capacitor COUT must be placed as close as possible to the pins VIN and VOUT
respectively.
3. Use short wires to connect the power supply to pins VIN and GND on the board.
9 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
Notes on Use
1. The input capacitor (CIN) and the output capacitor (COUT) should be placed to the as close as possible with a
shorter wiring.
2. If the impedance of the power supply is high, which is caused by forgetting installing input capacitor or installing
too small value capacitor, the oscillation may occur.
3. Please pay attention to the operation conditions of input and output voltage and load current, such that the
power consumption in the IC should not exceed the allowable power consumption of the package even though
the chip has short circuit protection.
IC has a built-in anti-static protection (ESD) circuit, but please do not add excessive stress to the IC.
Ordering Information
Part Name
Package
Marking
MD7671A50SF4
ESOP8
7671A
4000/ Tape & Reel
MD7671B50SF4
ESOP8
7671B
4000/ Tape & Reel
MD7671E50QC3
SOT23-5
7671
3000/ Tape & Reel
MD7671E33PA1
SOT89-3
7671E33
1000/ Tape & Reel
MD7671A33PA1
SOT89-3
7671A33
1000/ Tape & Reel
MD7671E50UB2
TO252-4
7671
2500/ Tape & Reel
10 / 14
Packing quantity
All packages
are lead-free
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
PACKAGING INFORMATION
ESOP8 PACKAGE OUTLINE DIMENSIONS
11 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
PACKAGING INFORMATION(CONTINUTED)
12 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
PACKAGING INFORMATION(CONTINUTED)
13 / 14
MD7671 Series
1A 5V-Adjustable Low Dropout Voltage Regulator
PACKAGING INFORMATION(CONTINUTED)
TO252-4L PACKAGE OUTLINE DIMENSIONS
www.md-ic.com.cn
For the newest datasheet, please see the website:
Version V1.1: 20201215
14 / 14