Preliminary
RT9166/A
300/600mA,
Ultra-Fast Transient Response LDO Regulator
General Description
The RT9166/A series are CMOS low dropout regulators
optimized for ultra-fast transient response. The devices are
capable of supplying 300mA
or 600mA of output current
with a dropout voltage of 230mV or 580mV respectively.
The RT9166/A series are is optimized for CD/DVD-ROM,
CD/RW or wireless communication supply applications.
The RT9166/A regulators are stable with output capacitors
as low as 1µF. The other features include ultra low dropout
voltage, high output accuracy, current limiting protection,
and high ripple rejection ratio.
The devices are available in fixed output voltages range of
1.2V to 4.5V with 0.1V per step. The RT9166/A regulators
are available in 3-lead SOT-23, SOT-89, SOT-223 and TO-92
packages.
Features
µ
Low Quiescent Current (Typically 220µA)
Guaranteed 300/600mA Output Current
Low Dropout Voltage: 230/580mV at 300/600mA
Wide Operating Voltage Ranges: 3V to 5.5V
Ultra-Fast Transient Response
Tight Load and Line Regulation
Current Limiting Protection
Thermal Shutdown Protection
Only low-ESR Ceramic Capacitor Required for
Stability
Custom Voltage Available
Applications
CD/DVD-ROM, CD/RW
Wireless LAN Card/Keyboard/Mouse
Battery-Powered Equipment
XDSL Router
PCMCIA Card
Ordering Information
RT9166/A -
Package Type
VL : SOT-23 (L-Type)
X : SOT-89
XL : SOT-89 (L-Type)
G : SOT-223
GL : SOT-223 (L-Type)
Z : TO-92
Pin Configurations
(TOP VIEW)
VIN
3
1
GND
2
VOUT
3
2
1
VOUT
GND
VIN
Operating Temperature Range
C : Commercial Standard
P : Pb Free with Commercial Standard
Output Voltage
12 : 1.2V
13 : 1.3V
:
45 : 4.5V
600mA Output Current
300mA Output Current
SOT-23 (L-Type)
(RT9166)
TO-92
(RT9166/A)
1
2
3
1
2
3
VOUT GND
(TAB)
VIN
GND
VIN VOUT
(TAB)
SOT-89
SOT-89 (L-Type)
Marking Information
For marking information, contact our sales representative
directly or through a RichTek distributor located in your
area, otherwise visit our website for detail.
1
2
3
1
2
3
VOUT GND
(TAB)
VIN
GND
VIN VOUT
(TAB)
SOT-223
DS9166/A-09 October 2004
SOT-223 (L-Type)
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1
RT9166/A
Typical Application Circuit
Preliminary
RT9166/A
V
IN
C
IN
1uF
VIN
VOUT
GND
C
OUT
1uF
V
OUT
Note: To prevent oscillation, a 1µF minimum X7R or X5R dielectric is strongly recommended if ceramics are
µ
used as input/output capacitors. When using the Y5V dielectric, the minimum value of the input/output
capacitance that can be used for stable over full operating temperature range is 3.3µF. (see Application
µ
Information Section for further details)
Functional Pin Description
Pin Name
VIN
VOUT
GND
Pin Function
Supply Input
Regulator Output
Common Ground
Function Block Diagram
VIN
Error
Amplifier
-
+
VOUT
Current
Limiting
Sensor
Thermal
Shutdown
1.2V
Reference
GND
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2
DS9166/A-09 October 2004
Preliminary
Absolute Maximum Ratings
(Note 1)
RT9166/A
Supply Input Voltage -------------------------------------------------------------------------------------------------- 6.5V
Power Dissipation, P
D
@ T
A
= 25°C
SOT-23 ------------------------------------------------------------------------------------------------------------------- 0.4W
SOT-89 ------------------------------------------------------------------------------------------------------------------- 0.571W
SOT-223 ----------------------------------------------------------------------------------------------------------------- 0.740W
Package Thermal Resistance (Note 7)
SOT-23,
θ
JA
------------------------------------------------------------------------------------------------------------- 250°C/W
SOT-89,
θ
JA
------------------------------------------------------------------------------------------------------------- 175°C/W
SOT-223,
θ
JA
------------------------------------------------------------------------------------------------------------ 135°C/W
Lead Temperature (Soldering, 10 sec.) --------------------------------------------------------------------------- 260°C
Junction Temperature ------------------------------------------------------------------------------------------------- 150°C
Storage Temperature Range ---------------------------------------------------------------------------------------- – 65°C to 150°C
ESD Susceptibility (Note 2)
HBM (Human Body Mode) ------------------------------------------------------------------------------------------ 2kV
MM (Machine Mode) -------------------------------------------------------------------------------------------------- 200V
Recommended Operating Conditions
(Note 3)
Supply Input Voltage -------------------------------------------------------------------------------------------------- 2.8V to 5.5V
Junction Temperature Range ---------------------------------------------------------------------------------------- – 40°C to 125°C
Electrical Characteristics
(V
IN
= V
OUT
+ 1V or V
IN
= 2.8V whichever is greater, C
IN
= 1µF, C
OUT
= 1µF, T
A
= 25°C, unless otherwise specified)
Parameter
Output Voltage Accuracy
Current Limit
Quiescent Current
Dropout Voltage
(Note 4)
Line Regulation
Load Regulation
(Note 5)
RT9166
RT9166A
RT9166
RT9166A
(Note 6)
RT9166
RT9166A
Symbol
∆V
OUT
I
LIM
I
Q
V
DROP
Test Conditions
I
OUT
= 1mA
R
LOAD
= 1Ω
I
OUT
= 0mA
I
OUT
= 300mA
I
OUT
= 600mA
V
IN
= (V
OUT
+ 0.3V) to 5.5V,
I
OUT
= 1mA
1mA
<
I
OUT
<
300mA
1mA
<
I
OUT
<
600mA
f = 1kHz, C
OUT
= 1µF
Min
−1
300
600
--
--
--
--
--
--
--
--
--
Typ
--
--
--
220
230
580
0.2
15
30
−55
170
40
Max
+3
--
--
300
--
--
--
35
55
--
--
--
Units
%
mA
µA
mV
∆V
LINE
∆V
LOAD
PSRR
T
SD
∆T
SD
%/V
mV
dB
°C
°C
Power Supply Rejection Rate
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
DS9166/A-09 October 2004
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3
RT9166/A
Preliminary
Note 1.
Stresses listed as the above
“Absolute
Maximum Ratings” may cause permanent damage to the device. These are for
stress ratings. 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 for extended
periods may remain possibility to affect device reliability.
Note 2.
Devices are ESD sensitive. Handling precaution recommended.
Note 3.
The device is not guaranteed to function outside its operating conditions.
Note 4.The
dropout voltage is defined as V
IN
-V
OUT
, which is measured when V
OUT
is V
OUT(NORMAL)
−
100mV.
Note 5.
Regulation is measured at constant junction temperature by using a 20ms current pulse. Devices are tested for load
regulation in the load range from 1mA to 300mA and 600mA respectively.
Note 6.
Quiescent, or ground current, is the difference between input and output currents. It is defined by I
Q
= I
IN
- I
OUT
under
no load condition (I
OUT
= 0mA). The total current drawn from the supply is the sum of the load current plus the ground
pin current.
Note 7.
θ
JA
is measured in the natural convection at T
A
= 25°C on a low effective thermal conductivity test board of
JEDEC 51-3 thermal measurement standard.
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4
DS9166/A-09 October 2004
Preliminary
Typical Operating Characteristics
Dropout Voltage vs. Load Current
700
600
RT9166/A
Power Supply Rejection Ratio
0
C
IN
= 1uF
C
OUT
= 1uF
T
J
= 125°C
-10
Dropout Voltage (mV)
V
IN
= 5V
C
IN
= 1uF
C
OUT
= 1uF
500
400
300
200
100
0
0
100
200
PSRR (dB)
T
J
= 25°C
-20
-30
-40
-50
-60
T
J
=
−40°C
100mA
1mA
300
400
500
600
10
100
1k
10k
100k
1M
Load Current (mA)
Frequency (Hz)
Region of Stable C
OUT
ESR vs. Load Current
100.00
Output Noise
V
IN
= 5V
C
IN
= 1uF
C
OUT
= 1uF to 4.7uF
10.00
I
LOAD
= 100mA
C
OUT
= 1uF
Output Noise Signal (µV)
Instable
400
200
0
-200
-400
f = 10Hz to 100KHz
C
OUT
ESR (Ω)
1.00
Stable
0.10
0.01
Instable
0.00
0
100
200
300
400
500
600
Time (1ms/DIV)
Load Current (mA)
Current Limit vs. Input voltage
900
Current Limit vs. Input voltage
900
Current Limit (mA)
800
Current Limit (mA)
850
850
800
750
V
IN
= 5V
C
IN
= 1uF
C
OUT
= 1uF
R
L
= 0.5
Ω
3
3.5
4
4.5
750
RT9166-33CX
700
5
5.5
700
V
IN
= 5V
C
IN
= 1uF
C
OUT
= 1uF
R
L
= 0.5
Ω
3
3.5
4
4.5
RT9166-33CVL
5
5.5
Input voltage (V)
DS9166/A-09 October 2004
Input voltage (V)
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