RT9182
RT9182
■ DESCRIPTION
The RT9182 series are highly accurate, Dual, low noise, CMOS LDO voltage regulators.
Performance features of the series includes low output noise, high ripple rejection ratio, low dropout and
very fast turn-on times.
The RT9182 includes a reference voltage source, error amplifiers, driver transistors, current
limiters and phase compensators internally. The RT9182’s current limiter’s foldback circuit also
operates as a short protect for the output current limiter. The output voltage for each regulator is set
independently by laser trimming. Voltages are selectable in 50mV steps within a range of 1.3V to 5.0V.
The EN function allows the output of each regulator to be turned off independently, resulting in
greatly reduced power consumption. The RT9182 series is available in the SOT-26.
■ FEATURES
l
l
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Output Voltage Range
Highly Accurate
Dropout Voltage
High Ripple Rejection
Low Power Consumption
Maximum Output Current
Standby Current
Internal protector
Small packages
1.3V to 6.0V (selectable in 50mV steps)
± 2%
200mV @ 100mA (3.0V type)
70dB (1 kHz)
25μA (TYP.)
300mA
less than 0.1μA
current limiter and short protector
SOT-26 and other required
■ APPLICATIONS
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Mobile phones
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Portable games
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Cordless phones and radio communication
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Portable AV equipment
equipment
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PDAs
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Cameras, Video cameras
■ PACKAGE
l
SOT-26
■ BLOCK DIAGRAM
Figure 1
■ ABSOLUTE MAXIMUM RATINGS
PARAMETER
SYMBOL
MAXIMUM RATING
VIN
VSS-0.3~VSS+10
VEN
VSS-0.3~VIN+0.3
Output Voltage
VOUT
VSS-0.3~VIN+0.3
Output Current
IOUT1+IOUT2
700
Power Dissipation
PD
Operating Ambient Temperature
Topr
-40~+85
Storage Temperature
Tstg
-40~+125
Input Voltage
UNIT
V
mA
SOT-26
250
mW
°C
Caution: The absolute maximum ratings are rated values exceeding which the product could suffer physical
damage. These values must therefore not be exceeded under any conditions.
■ Electrical Characteristics
Parameter
Symbol
Output Voltage
VOUT(E)
Output Current
IOUT
Dropout Voltage
Vdrop
Line Regulations
Temperature
Characteristics
MIN
VIN =VOUT(S)+1.0 V, IOUT=30
VOUT(S)
mA
×0.98
VIN≥VOUT(S)+1.0 V
300
—
—
IOUT=50 mA
—
0.06
0.10
IOUT=100 mA
—
0.20
0.30
—
0.01
0.2
∆VOUT 1
∆VIN • VOUT
VOUT(S)+0.5 V ≤VIN≤8 V
∆VOUT 2
VIN=VOUT(S)+1.0 V
Load Regulation
Output Voltage
CONDITION
∆VOUT
∆Ta • VOUT
Supply Current
ISS1
Standby Current
ISTB
Input Voltage
VIN
Ripple-Rejection
|PSRR|
Short-circuit
Current
Ishort
Current limiter
Ilim
CE “High” Voltage
VCEH
CE “Low” Voltage
VCEL
CE “High” Current
ICEH
CE “Low” Current
ICEH
■ TEST CIRCUITS
IOUT=30 mA
1.0 mA ≤IOUT ≤100 mA
TYP
VOUT(S)
MAX
VOUT(S)
×1.02
UNIT
CIRCUIT
V
1
mA
1
V
%/V
1
—
15
50
mV
—
±100
—
ppm/℃
—
25
40
μA
2
—
0.01
0.1
μA
3
2.0
—
10
V
—
—
70
—
dB
5
—
30
—
mA
1
—
450
—
mA
1
VIN
V
2
0.25
V
2
-0.1
0.1
uA
2
-0.1
0.1
uA
2
VIN=VOUT(S)+1.0 V, IOUT=10
mA
-40°C ≤ Ta ≤85°C
VIN=VOUT(S)+1.0 V
VIN=VEN=VOUT(T)+1V ,
VEN=VSS
——
VIN=VOUT(S)+1.0 V,f=1 kHz
Vrip=0.5 Vrms, IOUT=30 mA
VIN=VOUT(S)+1.0 V,
VIN=VEN
VIN=VEN=VOUT(T)+1V
1.3
VIN=VEN=VOUT(T)+1V
VIN=VEN=VOUT(T)+1V ,
VEN=VSS
■ TYPICAL APPLICATION CIRCUIT
Basic circuit
Caution The above connection diagram and constant will not guarantee successful operation. Perform thorough
evaluation using the actual application to set the constant.
■ Application Conditions
Input capacitor (CIN): 1.0µF or more
Output capacitor (CL): 1.0 µF or more (tantalum capacitor)
Caution A general series regulator may oscillate, depending on the external components selected. Check that no
oscillation occurs with the application using the above capacitor.
■ TYPICAL PERFORMANCE CHARACTERISTICS(3.0V output)
1.Output Voltage vs. Output Current
3.Dropout Voltage vs. Output Current
2.Output Voltage vs. Input Voltage (Contd.)
4.Dropout Voltage vs. Output Voltage
5.Output Voltage vs. Ambient Temperature
6.Ripple Rejection Rate
7.Transient Response
Input Transient Response
Load Transient Response
■ Ordering Information
RT9182 ①②③④⑤⑥⑦⑧
DESIGNATOR
①
②
■
DESCRIPTION
SYMBOL
DESCRIPTION
E
Active 'High' (pull-down resistor built in)
Regulator1
F
Active 'High' (no pull-down resistor built in)
EN type
G
Active 'Low' (pull-up resistor built in)
H
Active 'Low' (no pull-up resistor built in)
E
Active 'High' (pull-down resistor built in)
Regulator2
F
Active 'High' (no pull-down resistor built in)
EN type
G
Active 'Low' (pull-up resistor built in)
H
Active 'Low' (no pull-up resistor built in)
③④
Regulator1 Output Voltage
13~50
eg. 30 represents 3.0V
⑤⑥
Regulator2 Output Voltage
13~50
eg. 30 represents 3.0V
⑦
Packaging Types
M
SOT26
⑧
Device Orientation
R
Embossed tape: Standard feed
L
Embossed tape: Reverse feed
MARKING
● SOT-26
①Represents the product name
SYMBOL
1 PRODUCT NAME
RT9182◆◆◆◆◆◆M
◆
②③Represents internally set sequential number
Mark
②
③
Internally Set
Sequentially Number
C
2
C2
RT9182EE2025
C
0
C0
RT9182EE2520
0
1
01
RT9182FF2825
1
8
18
RT9182FF2528
Product Series
④Represents the assembly lot no.
0 to 9,A to Z, reversed character of 0 to 9 and A to Z repeated(G,I,J,O,Q W excepted)
■ PIN CONFIGURATION
■ PIN ASSIGNMENT
Pin Number
Pin Name
Function
4
EN1
ON/OFF Control1
5
VIN
Power Input
3
EN2
ON/OFF Control2
1
VOUT2
Output2
2
VSS
Ground
6
VOUT1
Output 1
SOT-26
■ PACKAGE INFORMATION
● SOT-26
RT9182
Preliminary
Dual, Low-Noise, 200mA LDO Regulator
General Description
Features
The RT9182 is a dual-channel, low noise, and low
• Up to 200mA Output Current (Each LDO)
dropout regulator supplying up to 200mA current at
each channel. The output voltage ranges from 1.5V
to 3.3V in 100mV increments and 2% accuracy by
• Shutdown Function
• 29µ
µVRMS Low Noise Output
• Current Limiting and Thermal Protection
operating from a +2.7V to +6.5V input.
• Short Circuit Protection
The RT9182 uses an internal PMOS as the pass
• Two LDOs in SOT-26 Package
device, which consumes 165µA supply current (both
LDOs on) independent of load current and dropout
• 120mV Dropout at 100mA Load
Applications
conditions. The SHDN pin controls both outputs
z
Cellular Phones
simultaneously and consumes nearly zero operation
z
Laptop, Notebook, and Palmtop Computers
current in the disable mode making the IC suitable
z
Battery-powered Equipment
for battery-power devices. Other features include a
z
Hand-held Equipment
reference voltage bypass pin to improve low noise
performance, current limiting, and over temperature
Pin Configurations
Part Number
protection.
Pin Configurations
TOP VIEW
RT9182…CE
Ordering Information
(Plastic SOT-26)
6
5
4
1
2
3
1.
2.
3.
4.
5.
6.
RT9182… … …
Package type
E : SOT-26
Operating temperature range
C : Commercial standard
Output voltage
A : 2.8V (Output1), 2.8V (Output2)
B : 3.0V (Output1), 3.0V (Output2)
VOUT2
GND
BP
SHDN
VIN
VOUT1
Typical Application Circuit
ON
OFF
VOUT2
Marking Information
VOUT2 VOUT1
2.2µF
Part Number
Marking
RT9182ACE
2M
RT9182BCE
2Q
DS9182-02 April 2002
SHDN
RT9182
BP
VIN
VOUT1
2.2µF
VIN
GND
10nF
2.2µF
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1
RT9182
Preliminary
Pin Description
Pin Name
Pin Function
VOUT2
Output2 Voltage
GND
Ground
BP
Reference Noise Bypass
SHDN
Active Low Shutdown Input
VIN
Power Input
VOUT1
Output1 Voltage
Function Block Diagram
Current Limit
Thermal Protection
Vref
+
+
_
Current Limit
_
VIN
VOUT1
VOUT2
Bias
BP
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2
Start-Up
GND
SHDN
DS9182-02 April 2002
RT9182
Preliminary
Absolute Maximum Ratings
z
Input Voltage
z
Power Dissipation, PD @ TA = 25°C
7V
SOT-26
748mW
z
Junction Temperature Range
-40°C ~ 125°C
z
Storage Temperature Range
-65°C ~ 150°C
z
Operating Temperature Range
-40°C ~ 85°C
z
Lead Temperature (Soldering, 10 sec.)
260°C
Electrical Characteristics
(VIN = 3.6V, CIN = COUT = 2.2µF, SHDN = VIN, typical values at TA = 25°C, for each LDO unless otherwise specified.)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
2.7
--
6.5
V
-2
--
+2
%
Input Voltage Range
VIN
Output Voltage Accuracy
(Load Regulation)
∆VOUT
IL = 1mA to 200mA
Maximum Output Current
IMAX
Continuous
200
--
--
mA
Current Limit
ILIMIT
RLOAD = 1Ω
200
--
550
mA
GND Pin Current
No Load
--
165
260
IG
µA
IOUT = 100mA (Both LDOs)
--
165
260
µA
IOUT = 1mA
--
1.2
--
mV
IOUT = 100mA
--
120
--
mV
IOUT = 200mA
--
255
--
mV
Dropout Voltage
(Note)
VDROP
Line Regulation
∆VLINE
VIN = (VOUT +0.4V or 2.7V) to 6.5V
IOUT = 1mA
-0.2
--
+0.2
%/V
SHDN Input High Threshold
VIH
VIN = 2.7V to 6.5V
1.6
--
--
V
SHDN Input Low Threshold
VIL
VIN = 2.7V to 6.5V
--
--
0.4
V
SHDN Input Bias Current
ISD
SHDN = GND or VIN
--
--
100
nA
Shutdown Supply Current
IGSD
SHDN = GND
--
0.01
1
µA
--
140
--
°C
--
10
--
°C
10Hz to 100kHz, CBP = 10nF
COUT = 4.7µF, ILOAD = 1mA
--
29
--
µVRMS
100Hz, CBP = 10nF, COUT = 4.7µF
ILOAD = 100mA
--
62
--
dB
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
TSD
Output Voltage Noise
eNO
Output Voltage AC PSRR
Note : Dropout voltage definition: VIN – VOUT when VOUT is 50mV below the value of VOUT (normal)
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3
RT9182
Preliminary
Typical Operating Characteristics
VOUT = 2.8V, ILOAD = 100mA, VIN = 3.6V, COUT = 4.7µF, CBP = 10nF, and CIN = 2.2µF, unless otherwise noted.
Quiescent Current vs. Supply Voltage
Output Voltage Accuracy vs. Temp.
240
1.0
No Load
160
ILoad = 100mA, both outputs
0.6
120
80
Output Voltage (%)
Quiescent Current (µ A)
0.8
200
0.4
0.2
0.0
-0.2
-0.4
-0.6
40
-0.8
-1.0
0
2.5
3.5
4.5
5.5
-40
6.5
-15
10
35
60
85
Temperature ( ° C)
Supply Voltage (V)
Dropout Voltage vs. Temp.
Quiescent Current vs. Load Current
300
180
Both outputs loaded
250
Dropout Voltage (mV)
Quiescent Current (µ A)
150
120
90
60
200
150
100
30
50
0
0
ILOAD = 200mA
0
40
80
120
160
-40
200
-15
10
35
60
85
Temperature ( ° C)
Load Current (mA)
PSRR vs. Frequency
Quiescent Current vs. Temp.
200
70
175
60
150
50
PSRR (dB)
Quiescent Current ( µ A)
ILOAD = 1mA
125
100
75
30
20
50
10
25
0
0
-40
-15
10
35
Temperature ( °C)
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4
40
60
85
10
100
1K
10K
100K
1M
Frequency (Hz)
DS9182-02 April 2002
RT9182
Preliminary
Channel-to-Channel Isolation
vs. Frequency
Noise Density vs. Frequency
120
10K
Noise Density (nV/ Hz)
Channel Isolation (dB)
100
80
60
40
1K
100
20
RLOAD = 100Ω
1K
10K
100K
10K
Load Transient Response
(ILOAD = 0 to 80mA)
≈
≈
TT
T
Peak value depends on COUT ESR
≈
≈
2>
TT
10µS/Div
Time
50µS/Div
Time
Shutdown Response
ILOAD = 1mA
5V/Div
2>
DS9182-02 April 2002
TT
1mS/Div
Time
100µV/Div
≈
Output Voltage (AC-Coupled)
1V/Div
T
≈
COUT = 2.2µF
Output Noise (10Hz to 100kHz)
ILOAD = 50mA
1>
100K
1>
100mA/Div
20mV/Div
1>
50mV/Div
Line Transient Response
2↓
Output Voltage
1K
Frequency (Hz)
3.5
Shutdown Voltage
100
Frequency (Hz)
T
4.5
10
10
1M
Output Voltage Deviation
(AC-Coupled)
100
Load Current
Input Voltage (V)
Output Voltage Deviation
(AC-Coupled)
0
T
1>
1mS/Div
Time
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RT9182
Preliminary
Functional Description
The RT9182 is integrated with two low noise, low
event of fault conditions. Do not exceed the absolute
dropout, and low quiescent current linear regulators
maximum junction-temperature rating of TJ = +150°C
designed primarily for battery-powered applications.
for continuous operation. The output can be shorted
Output voltages are optional ranging from 1.5V to
to ground for an indefinite amount of time without
3.3V, and each channel can supply current up to
damaging the part by cooperation of current limit and
200mA.
thermal protection.
Shutdown
Operating Region and Power Dissipation
The RT9182 is shutdown by pulling the SHDN input
The maximum power dissipation of RT9182 depends
low, and turned on by driving the input high. If this
on the thermal resistance of the case and circuit
feature is not to be used, the SHDN input should be
board, the temperature difference between the die
tied to VIN to keep the regulator on at all times (the
junction and ambient air, and the rate of airflow. The
SHDN input must not be left floating).
power dissipation across the device is
P = IOUT (VIN - VOUT).
Internal P-Channel Pass Transistor
The RT9182 features double typical 1.5Ω P-channel
MOSFET
pass
transistors. It provides
several
advantages over similar designs using PNP pass
transistors, including longer battery life. The P-
The maximum power dissipation is:
PMAX = (TJ - TA) / θJA
where TJ - TA is the temperature difference between
the RT9182 die junction and the surrounding
channel MOSFET requires no base drive, which
environment, θJA is the thermal resistance from the
reduces quiescent current considerably. PNP-based
junction to the surrounding environment. The GND
regulators waste considerable current in dropout
pin of the RT9182 performs the dual function of
when the pass transistor saturates. They also use
providing an electrical connection to ground and
high base-drive currents under large loads. The
channeling heat away. Connect the GND pin to
RT9182 does not suffer from these problems and
ground using a large pad or ground plane.
consume only 165µA of quiescent current whether in
dropout, light-load, or heavy-load applications.
Low-Noise Operation
An external 10nF bypass capacitor at BP, in
Current Limit and Thermal Protection
conjunction with an internal resistor, creates a
The RT9182 includes two independent current limit
lowpass filter. The RT9182 exhibits 29µVRMS of
structure which monitor and control each pass
output voltage noise with CBP = 10nF and COUT =
transistor’s gate voltage limiting the guaranteed
2.2µF.
maximum output current to 200mA minimum.
Thermal-overload
protection
limits
total
power
dissipation in the RT9182. When the junction
temperature exceeds TJ = +140°C, the thermal
sensor signals the shutdown logic turning off the
pass transistor and allowing the IC to cool. The
thermal sensor will turn the pass transistor on again
after the IC’s junction temperature cools by 10°C,
resulting in a pulsed output during continuous
thermal-overload
conditions.
Thermal-overloaded
protection is designed to protect the RT9182 in the
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DS9182-02 April 2002
RT9182
Preliminary
Applications Information
Capacitor Selection and Regulator Stability
Like
any
low-dropout
regulator,
the
external
rating
sufficient
for
the
application
by
the
manufacture.
capacitors used with the RT9182 must be carefully
selected for regulator stability and performance.
Region of Stable COUT ESR vs. Load Current
100
COUT = 4.7µF
Using a capacitor whose value is > 1µF on the
RT9182 input and the amount of capacitance can be
located a distance of not more than 0.5" from the
input pin of the IC and returned to a clean analog
ground. Any good quality ceramic or tantalum can be
used for this capacitor. The capacitor with larger
10
COUT ESR (mΩ)
(Ω)
Ω
increased without limit. The input capacitor must be
COUT = 1µF
1
0.1
value and lower ESR (equivalent series resistance)
provides better PSRR and line-transient response.
The output capacitor must meet both requirements
for minimum amount of capacitance and ESR in all
0.01
0.001
0
40
80
120
LDO applications (see Fig.1). The RT9182 is
Load Current (mA)
designed specifically to work with low ESR ceramic
Fig. 1
160
200
output capacitor in space-saving and performance
consideration. Using a ceramic capacitor whose
Use a 10nF bypass capacitor at BP pin for low output
value is at least 1µF with ESR is > 5mΩ on the
voltage noise. The capacitor, in conjunction with an
RT9182 output ensures stability. The RT9182 still
internal resistor, which connects bypass pin and the
works well with output capacitor of other types due to
band-gap reference, creates a low-pass filter for
the wide stable ESR range. Output capacitor of larger
noise reduction. Increasing the capacitance will
capacitance can reduce noise and improve load-
slightly decrease the output noise, and it is almost
transient response, stability, and PSRR. The output
independent of the start-up time. The capacitor
capacitor should be located not more than 0.5"
connected to the bypass pin for noise reduction must
from the VOUT pin of the RT9182 and returned to a
have very low leakage. This capacitor leakage
clean analog ground.
current causes the output voltage to decline by a
proportional amount to the current.
Note that some ceramic dielectrics exhibit large
capacitance and ESR variation with temperature. It
Load-Transient Considerations
may be necessary to use 2.2µF or more to ensure
The RT9182 load-transient response graphs show
stability at temperatures below -10°C in this case.
two components of the output response: a DC shift
Also, tantalum capacitors, 2.2µF or more may be
from the output impedance due to the load current
needed to maintain capacitance and ESR in the
change, and the transient response. The DC shift is
stable region for strict application environment.
quite small due to the excellent load regulation of the
IC. Typical output voltage transient spike for a step
Tantalum capacitors maybe suffer failure due to
change in the load current from 0mA to 50mA is tens
surge current when it is connected to a low-
mV, depending on the ESR of the output capacitor.
impedance source of power (like a battery or very
Increasing
large capacitor). If a tantalum capacitor is used at the
decreasing the ESR attenuates the overshoot.
the
output
capacitor’s
value
and
input, it must be guaranteed to have a surge current
DS9182-02 April 2002
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7
RT9182
Preliminary
Input-Output (Dropout) Voltage
A
regulator’s
minimum
input-output
voltage
differential (or dropout voltage) determines the lowest
usable supply voltage. In battery-powered systems,
this will determine the useful end-of-life battery
voltage. Because the RT9182 uses a P-channel
MOSFET pass transistor, the dropout voltage is a
function of drain-to-source on-resistance [RDS(ON)]
multiplied by the load current.
Reverse Current Path
The power transistor used in the RT9182 has an
inherent diode connected between each regulator
input and output (see Fig.2). If the output is forced
above the input by more than a diode-drop, this diode
will become forward biased and current will flow from
the VOUT terminal to VIN. This diode will also be
turned on by abruptly stepping the input voltage to a
value below the output voltage. To prevent regulator
mis-operation, a Schottky diode could be used in the
applications where input/output voltage conditions
can cause the internal diode to be turned on (see
Fig.3). As shown, the Schottky diode is connected in
parallel with the internal parasitic diode and prevents
it from being turned on by limiting the voltage drop
across it to about 0.3V < 100mA to prevent damage
to the part.
VIN
VOUT
Fig. 2
VIN
VOUT
Fig. 3
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DS9182-02 April 2002
RT9182
Preliminary
Package Information
D
C
B
b
H
A
A1
e
Symbol
L
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.889
1.295
0.035
0.051
A1
--
0.152
--
0.006
B
1.397
1.803
0.055
0.071
b
0.356
0.559
0.014
0.022
C
2.591
2.997
0.102
0.118
D
2.692
3.099
0.106
0.122
e
0.838
1.041
0.033
0.041
H
0.102
0.254
0.004
0.010
L
0.356
0.610
0.014
0.024
SOT- 26 Surface Mount Package
DS9182-02 April 2002
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9
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