DS9083 03

®
RT9083
30μ
μA IQ, 250mA Low-Dropout Linear Regulator
General Description
Features
The RT9083 is a low-dropout (LDO) voltage regulators with
enable function that operates from 1.2V to 5.5V. It provides
up to 250mA of output current and offers low-power
operation in miniaturized packaging.

The features of low quiescent current as low as 30μA and
almost zero disable current is ideal for powering the battery
equipment to a longer service life. The RT9083 is stable
with the ceramic output capacitor over its wide input range
from 1.2V to 5.5V and the entire range of output load
current (0mA to 250mA).








Ordering Information
RT9083/NPackage Type
J5 : TSOT-23-5




30μ
μA Ground Current
PSRR = 75dB at 1kHz
Adjustable Output Voltage Available by Specific
Application
±2% Output Accuracy
250mA (VIN ≥ 2.3V) Output Current with EN
Low (0.1μ
μA) Disable Current
1.2V to 5.5V Operating Input Voltage
Dropout Voltage : 0.45V (typ.) at 250mA when
VOUT ≥ 3V
Support Fixed Output Voltage 0.9V, 1.05V, 1.2V, 1.5V,
1.8V, 1.9V, 2.5V, 2.7V, 2.8V, 2.9V, 3V, 3.3V
Stable with Ceramic or Tantalum Capacitor
Current Limit Protection
Over Temperature Protection
TSOT-23-5 Packages Available
Lead Plating System
G : Green (Halogen Free and Pb Free) Applications
Output Voltage
09 : 0.9V
:
33 : 3.3V
Special Request : Any Voltage
Between 0.9V and 3.3V under
specific business agreement
Pin Function
RT9083 : With SNS Pin
RT9083N : Without SNS Pin



Portable, Battery Powered Equipment
Ultra Low Power Microcontrollers
Notebook computers
Marking Information
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
Note :
Richtek products are :

RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020.

Suitable for use in SnPb or Pb-free soldering processes.
Copyright © 2016 Richtek Technology Corporation. All rights reserved.
DS9083-03
June 2016
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1
RT9083
Pin Configurations
(TOP VIEW)
VOUT
SNS/NC
5
4
2
3
VIN GND EN
TSOT-23-5
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
VIN
Supply Voltage Input.
2
GND
Ground.
3
EN
Enable Control Input.
SNS
Output Voltage Sense.
NC
No Internal Connection. (RT9083N only)
VOUT
Output of the Regulator.
4
5
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June 2016
RT9083
Function Block Diagram
VIN
(without sense
function)
Current/Thermal
Sense
GND
SNS
(with sense
function)
Bandgap
Reference
+
-
EN
VOUT
R1
R2
Operation
Basic Operation
Current Limit Protection
The RT9083 is a low quiescent current linear regulator
designed especially for low external components system.
The input voltage range is from 1.2V to 5.5V.
The RT9083 provides current limit function to prevent the
device from damages during over-load or shorted-circuit
condition. This current is detected by an internal sensing
transistor.
The minimum required output capacitance for stable
operation is 1μF effective capacitance after consideration
of the temperature and voltage coefficient of the capacitor.
Output Transistor
The RT9083 builds in a P-MOSFET output transistor which
provides a low switch-on resistance for low dropout voltage
applications.
Over Temperature Protection
The over temperature protection function will turn off the
P-MOSFET when the junction temperature exceeds 150°C
(typ.), VIN ≥ 1.5V and the output current exceeds 30mA.
Once the junction temperature cools down by
approximately 20°C, the regulator will automatically
resume operation.
Error Amplifier
The Error Amplifier compares the internal reference voltage
with the output feedback voltage from the internal divider,
and controls the Gate voltage of P-MOSFET to support
good line regulation and load regulation at output voltage.
Enable
The RT9083 delivers the output power when it is set to
enable state. When it works in disable state, there is no
output power and the operation quiescent current is almost
zero.
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June 2016
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3
RT9083
Absolute Maximum Ratings








(Note 1)
VIN, VOUT, SNS, EN to GND ------------------------------------------------------------------------------------------- −0.3V to 6.5V
VOUT to VIN ---------------------------------------------------------------------------------------------------------------- −6.5V to 0.3V
Power Dissipation, PD @ TA = 25°C
TSOT-23-5 ------------------------------------------------------------------------------------------------------------------- 0.43W
Package Thermal Resistance (Note 2)
TSOT-23-5, θJA ------------------------------------------------------------------------------------------------------------- 230.6°C/W
Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------- 260°C
Junction Temperature ----------------------------------------------------------------------------------------------------- 150°C
Storage Temperature Range -------------------------------------------------------------------------------------------- −65°C to 150°C
ESD Susceptibility (Note 3)
HBM (Human Body Model) ---------------------------------------------------------------------------------------------- 2kV
MM (Machine Model) ------------------------------------------------------------------------------------------------------ 200V
Recommended Operating Conditions



(Note 4)
Input Voltage, VIN --------------------------------------------------------------------------------------------------------- 1.2V to 5.5V
Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C
Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VOUT + 1 < VIN < 5.5V, TA = 25°C, unless otherwise specified)
Parameter
Output Voltage Range
Symbol
Dropout Voltage
(ILOAD = 250mA)
(Note 5)
(Note 5)
VCC Consumption Current
Min
Typ
Max
Unit
0.9
--
3.3
V
ILOAD = 1mA
2
--
2
%
0.9V  VOUT  1.2V
--
0.5
0.65
1.2V  VOUT  1.5V
--
0.3
0.4
1.5V  VOUT  1.8V
--
0.2
0.24
1.8V  VOUT  2.5V
--
0.15
0.18
2.5V  VOUT  3V
--
0.1
0.15
3V  VOUT
--
0.08
0.12
0.9V  VOUT  1.2V
--
1.25
1.45
1.2V  VOUT  1.5V
--
1
1.2
1.5V  VOUT  1.8V
--
0.81
0.9
1.8V  VOUT  2.5V
--
0.68
0.8
2.5V  VOUT  3V
--
0.51
0.6
3V  VOUT
--
0.45
0.6
ILOAD = 20mA, VOUT ≦ 5.5V
--
30
50
VOUT
DC Output Accuracy
Dropout Voltage
(ILOAD = 50mA)
Test Conditions
VDROP
VDROP
IQ
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V
V
A
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DS9083-03
June 2016
RT9083
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
Shutdown GND Current
VEN = 0V
--
0.1
0.5
A
Shutdown Leakage Current
VEN = 0V, VOUT = 0V
--
0.1
0.5
A
VEN = 5.5V
--
--
0.1
A
1.2V  VIN  1.5V
--
--
0.6
1.5V  VIN  1.8V
--
--
0.5
1.8V  VIN  2.1V
--
--
0.3
2.1V  VIN  5.5V
--
--
0.15
EN Input Current
IEN
LINE
Line Regulation
ILOAD = 10mA
%
Load Regulation
LOAD
5mA < ILOAD < 250mA
--
--
1
%
Power Supply Rejection
Ratio
PSRR
VIN = 3V, ILOAD = 50mA,
COUT = 1F, VOUT = 2.5V, f = 1kHz
--
75
--
dB
VOUT = 0.9V
--
39
--
VOUT = 1.2V
--
46
--
VOUT = 1.8V
--
48
--
VOUT = 3.3V
--
58
--
Peak output current
260
350
500
mA
VOUT = 0.5V x VOUT(normal)
150
270
390
mA
COUT = 1F,
ILOAD = 30mA,
BW = 10Hz to
100kHz,
VIN = VOUT + 2V
Output Voltage Noise
Output Current Limit
ILIM
Fold-Back Current Limit
VRMS
Logic-High
VIH
VIN = 5V
1.2
--
--
Logic-Low
VIL
VIN = 5V
--
--
0.4
Thermal Shutdown
Temperature
TSD
ILOAD = 30mA, VIN  1.5V
--
150
--
C
Thermal Shutdown
Hysteresis
TSD
--
20
--
C
Enable Input
Voltage
V
Note 1. Stresses beyond those listed “Absolute Maximum Ratings” may cause permanent damage to the device. These are
stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in
the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may
affect device reliability.
Note 2. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7.
Note 3. Devices are ESD sensitive. Handling precaution is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
Note 5. The dropout voltage is defined as VIN − VOUT, when VOUT is 98% of the normal value of VOUT.
Copyright © 2016 Richtek Technology Corporation. All rights reserved.
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June 2016
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5
RT9083
Typical Application Circuit
RT9083
VIN
CIN
1µF
EN
VIN
VOUT
VOUT
COUT
(Effective Capacitance
SNS
 1µF)
EN
GND
Figure 1. Application with Sense Function
RT9083N
VIN
CIN
1µF
EN
VIN
VOUT
VOUT
COUT
(Effective Capacitance
 1µF)
EN
GND
Figure 2. Application without Sense Function
RT9083
VIN
CIN
1µF
VIN
VOUT
VOUT
R1
SNS
EN
EN
NC
COUT
(Effective Capacitance
 1µF)
R2
GND
Figure 3. Adjustable Output Voltage Application Circuit
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is a registered trademark of Richtek Technology Corporation.
DS9083-03
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RT9083
Typical Operating Characteristics
Output Voltage vs. Temperature
Output Voltage vs. Temperature
0.91
3.32
0.90
Output Voltage (V)
Output Voltage (V)
3.31
3.30
3.29
ILOAD = 1mA
ILOAD = 250mA
3.28
3.27
ILOAD = 1mA
ILOAD = 250mA
0.89
0.88
0.87
3.26
VIN = 5V VOUT = 3.3V
VIN = 5V VOUT = 0.9V
0.86
3.25
-50
-25
0
25
50
75
100
-50
125
-25
0
25
50
75
100
125
Temperature (°C)
Temperature (°C)
Output Voltage vs. Input Voltage
Output Voltage vs. Output Current
3.33
0.904
0.902
Output Voltage (V)
Outout Voltage (V)
3.32
0.900
0.898
0.896
0.894
3.31
3.3
3.29
0.892
VOUT = 0.9V, ILOAD = 1mA
VIN = 5V VOUT = 3.3V
0.890
3.28
1
1.5
2
2.5
3
3.5
4
4.5
5
0
5.5
30
Input Voltage (V)
60
90
120
150
180
210
240
Output Current (mA)
Ground Current vs. Input Voltage
Ground Current vs. Temperature
34
35
Ground Current (μA)
Ground Current (μA)
32
30
28
26
24
22
30
25
20
15
VOUT = 0.9V, ILOAD = 20mA
20
2.3
2.8
3.3
3.8
4.3
4.8
Input Voltage (V)
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VIN = 5V, VOUT = 0.9V, ILOAD = 20mA
10
June 2016
5.3
-50
-25
0
25
50
75
100
125
Temperature (°C)
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RT9083
Shutdown Current vs. Temperature
Shutdown Current vs. Input Voltage
0.50
VOUT = 0.9V, VEN = 0V
Shutdown Current (μA)1
0.45
Shutdown Current (μA)1
0.30
0.40
0.35
0.30
0.25
0.20
0.15
0.10
VEN = 0V
0.25
0.20
0.15
0.10
VIN = 5V
VIN = 3.5V
0.05
0.05
0.00
0.00
1.2 1.6
2
2.4 2.8 3.2 3.6
4
-50
4.4 4.8 5.2 5.6
-25
0
Input Voltage (V)
EN Threshold vs. Input Voltage
0.70
25
50
75
100
125
Temperature (°C)
EN Threshold vs. Temperature
1.00
EN_H
0.60
0.80
EN_L
EN Threshold (V)
EN Threshold (V)
0.65
0.55
0.50
0.45
0.40
EN_H
0.60
EN_L
0.40
0.20
0.35
VIN = 5V
0.30
0.00
1.2 1.6
2
2.4 2.8 3.2 3.6
4
4.4 4.8 5.2 5.6
-50
-25
0
Dropout Voltage vs. Temperature
0.40
50
75
100
125
Dropout Voltage vs. Output Current
1.6
VOUT = 3.3V
0.35
VOUT = 0.9V
1.4
0.30
0.25
Dropout Voltage (V)
Dropout Voltage (V)
25
Temperature (°C)
Input Voltage (V)
ILOAD = 100mA
0.20
0.15
ILOAD = 50mA
0.10
ILOAD = 20mA
0.05
1.2
1.0
TA = 125°C
TA = 85°C
TA = 25°C
TA = −40°C
0.8
0.6
0.4
0.2
0.00
0.0
-50
-25
0
25
50
75
100
Temperature (°C)
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125
0
50
100
150
200
250
Output Current (mA)
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June 2016
RT9083
Dropout Voltage vs. Output Current
Dropout Voltage vs. Output Current
1.4
1.2
VOUT = 1.5V
1.0
Dropout Voltage (V)
Dropout Voltage (V)
1.2
VOUT = 2.5V
1.0
0.8
0.6
TA = 125°C
TA = 85°C
TA = 25°C
TA = −40°C
0.4
0.2
0.8
TA = 125°C
TA = 85°C
TA = 25°C
TA = −40°C
0.6
0.4
0.2
0.0
0.0
0
50
100
150
200
0
250
50
420
Fold-Back Current Limit (mA)
VIN = 5V
Current Limit (mA)
480
VOUT = 0.9V
380
VOUT = 3.3V
330
200
250
Fold-Back Current Limit vs. Temperature
Current Limit vs. Temperature
430
150
Output Current (mA)
Output Current (mA)
530
100
VIN = 5V
370
VOUT = 0.9V
320
VOUT = 3.3V
270
220
280
-50
-25
0
25
50
75
100
125
-50
-25
0
25
50
75
100
125
Temperature (°C)
Temperature (°C)
SNS Input Current vs. Temperature
Power On from EN
SNS Input Current (nA)
700
VOUT = 0.9V
VOUT = 3.3V
600
VIN
(2V/Div)
VEN
(2V/Div)
VOUT
(2V/Div)
500
VIN = 5V
I LOAD
(100mA/Div)
VIN = 5V
400
-50
-25
0
25
50
75
100
125
Time (50μs/Div)
Temperature (°C)
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June 2016
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9
RT9083
Line Transient
Power Off from EN
VIN
(2V/Div)
VEN
(2V/Div)
VOUT
(2V/Div)
VIN
(2V/Div)
VOUT
(5mV/Div)
I LOAD
(100mA/Div)
VIN = 2.4V to 5.5V, VOUT = 0.9V, ILOAD = 10mA
VIN = 5V
Time (250μs/Div)
Time (25μs/Div)
Load Transient
PSRR vs. Frequency
0
VIN
(200mV/Div)
VIN = 3.5V, ILOAD = 150mA
VIN = 3V, ILOAD = 50mA
VIN = 3.5V, ILOAD = 50mA
PSRR (dB)
-20
-40
-60
-80
I LOAD
(100mA/Div)
VIN = 5V, VOUT = 3.3V, ILOAD = 10mA to 250mA
-100
Time (250μs/Div)
10
100
1000
10000
100000
1000000
Frequency (Hz)
Output Noise
VIN = 2.9V, VOUT = 0.9V, ILOAD = 100mA
COUT = 1μF, f = 10Hz to 100kHz
Noise (μV)
Noise (μV)
Output Noise
300
270
240
210
180
150
120
90
60
30
0
-30
-60
-90
-120
-150
-180
-210
-240
-270
-300
0
1
2
3
4
5
6
7
8
9
sec (m)
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10
300
270
240
210
180
150
120
90
60
30
0
-30
-60
-90
-120
-150
-180
-210
-240
-270
-300
VIN = 5.3V, VOUT = 3.3V, ILOAD = 100mA
COUT = 1μF, f = 10Hz to 100kHz
0
1
2
3
4
5
6
7
8
9
10
sec (m)
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RT9083
Application Information
Enable
Output Voltage vs. Temperature
3.30
3.29
3.28
3.27
ILOAD = 1mA
3.26
3.25
3.24
3.23
3.22
The RT9083 has an EN pin to turn on or turn off the
regulator, When the EN pin is in logic high, the regulator
will be turned on. The shutdown current is almost 0μA
typical. The EN pin may be directly tied to VIN to keep the
part on. The Enable input is CMOS logic and cannot be
left floating.
Adjustable Output Voltage Setting
Because of the small input current at the SNS pin, the
RT9083 with SNS pin also can work as an adjustable output
voltage LDO. Figure 3 gives the connections for the
adjustable output voltage application. The resistor divider
from VOUT to SNS sets the output voltage when in
regulation.
The voltage on the SNS pin sets the output voltage and is
determined by the values of R1 and R2. In order to keep
a good temperature coefficient of output voltage, the values
of R1 and R2 should be selected carefully to ignore the
temperature coefficient of input current at the SNS pin. A
current greater than 50μA in the resistor divider is
recommended to meet the above requirement. The
adjustable output voltage can be calculated using the
formula given in equation 1 :
VOUT  R1 + R2  VSNS
(1)
R2
where VSNS is determined by the output voltage selections
in the ordering information of RT9083.
When we choose 39kΩ and 15kΩ as R1 and R2
respectively, and select a 0.9V output at SNS pin, the
adjustable output voltage will be set to around 3.24V. Its
Copyright © 2016 Richtek Technology Corporation. All rights reserved.
DS9083-03
temperature coefficient in Figure 4 is still perfect in such
kind of application.
Output Voltage (V)
Like any low dropout linear regulator, the RT9083’s
external input and output capacitors must be properly
selected for stability and performance. Use a 1μF or larger
input capacitor and place it close to the IC's VIN and GND
pins. Any output capacitor meeting the minimum 1mΩ
ESR (Equivalent Series Resistance) and effective
capacitance larger than 1μF requirement may be used.
Place the output capacitor close to the IC's VOUT and
GND pins. Increasing capacitance and decreasing ESR
can improve the circuit's PSRR and line transient response.
June 2016
3.21
3.20
-50
-25
0
25
50
75
100
125
Temperature (°C)
Figure 4. Temperature Coefficient of Adjustable Output
Voltage
The minimum recommended 50μA in the resistor divider
makes the application no longer an ultra low quiescent
LDO. Figure 5 is another fine adjustable output voltage
application can keep the LDO still operating in low power
consumption. The fine fune range is recommended to be
less than 50mV (R1 ≤ 91kΩ) in order to keep a good
temperature coefficient of the output voltage.
RT9083
1µF
VIN
VOUT
R1
SNS
56pF/NC
1µF
EN
GND
Figure 5. Fine Adjustable Output Voltage Application
Circuit
There isn't extra current consumption in the above
application. But the temperature coefficient of output
voltage will be degraded by the input current at SNS pin.
If the tuning range is larger than 50mV, a compensation
capacitor (56pF) is required to keep the stability of output
voltage. The fine adjustable output voltage is calculated
using the formula given in equation2 :
VOUT  VSNS + ISNS  R1
(2)
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RT9083
Current Limit
The RT9083 contains an independent current limiter, which
monitors and controls the pass transistor's gate voltage,
limiting the output current to 0.35A (typ.). The current
limiting level is reduced to around 250mA named fold-back
current limit when the output voltage is further decreased.
The output can be shorted to ground indefinitely without
damaging the part.
Thermal Considerations
1.0
Maximum Power Dissipation (W)1
where ISNS is the input Current at SNS pin (typical 550nA
at room temperature) and VSNS is determined by the
output voltage selections in the ordering information of
RT9083.
Four-Layer PCB
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 6. Derating Curve of Maximum Power Dissipation
For continuous operation, do not exceed absolute
maximum junction temperature. The maximum power
dissipation depends on the thermal resistance of the IC
package, PCB layout, rate of surrounding airflow, and
difference between junction and ambient temperature. The
maximum power dissipation can be calculated by the
following formula :
PD(MAX) = (TJ(MAX) − TA) / θJA
where TJ(MAX) is the maximum junction temperature, TA is
the ambient temperature, and θJA is the junction to ambient
thermal resistance.
For recommended operating condition specifications the
maximum junction temperature is 125°C and TA is the
ambient temperature. The junction to ambient thermal
resistance, θJA, is layout dependent. For TSOT-23-5
package, the thermal resistance, θJA, is 230.6°C/W on a
standard JEDEC 51-7 four-layer thermal test board. The
maximum power dissipation at TA = 25°C can be calculated
by the following formula :
PD(MAX) = (125°C − 25°C) / (230.6°C/W) = 0.43W for
TSOT-23-5 package
The maximum power dissipation depends on the operating
ambient temperature for fixed T J(MAX) and thermal
resistance, θJA. The derating curve in Figure 6 allows the
designer to see the effect of rising ambient temperature
on the maximum power dissipation.
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June 2016
RT9083
Outline Dimension
H
D
L
B
C
b
A
A1
e
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.700
1.000
0.028
0.039
A1
0.000
0.100
0.000
0.004
B
1.397
1.803
0.055
0.071
b
0.300
0.559
0.012
0.022
C
2.591
3.000
0.102
0.118
D
2.692
3.099
0.106
0.122
e
0.838
1.041
0.033
0.041
H
0.080
0.254
0.003
0.010
L
0.300
0.610
0.012
0.024
TSOT-23-5 Surface Mount Package
Richtek Technology Corporation
14F, No. 8, Tai Yuen 1st Street, Chupei City
Hsinchu, Taiwan, R.O.C.
Tel: (8863)5526789
Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should
obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot
assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnished by Richtek is believed to be
accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries.
DS9083-03
June 2016
www.richtek.com
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