RICHTEK RT9166

RT9166/A
300/600mA, Ultra-Fast Transient Response LDO Regulator
General Description
Features
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.
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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.
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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, TO-92
and TO-252 packages.
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Ordering Information
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RT9166/A-
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Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commercial Standard)
Only Low-ESR Ceramic Capacitor Required for
Stability
Custom Voltage Available
RoHS Compliant and 100% Lead (Pb)-Free
Applications
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Package Type
VL : SOT-23-3 (L-Type)
X : SOT-89
XL : SOT-89 (L-Type)
G : SOT-223
GL : SOT-223 (L-Type)
Z : TO-92
L : TO-252
μA)
Low Quiescent Current (Typically 220μ
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
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CD/DVD-ROM, CD/RW
Wireless LAN Card/Keyboard/Mouse
Battery-Powered Equipment
XDSL Router
PCMCIA Card
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.
Pin Configurations
(TOP VIEW)
Output Voltage
12 : 1.2V
13 : 1.3V
:
45 : 4.5V
1B : 1.25V
VIN
3
1
2
GND
VOUT
SOT-23-3 (L-Type)
(RT9166)
600mA Output Current
300mA Output Current
Note :
RichTek Pb-free and Green 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.
3
VOUT
2
GND
1
VIN
TO-92
(RT9166/A)
`100%matte tin (Sn) plating.
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RT9166/A
1
2
VOUT GND
(TAB)
3
1
VIN
GND
2
3
1
VIN VOUT
(TAB)
SOT-89 (L-Type)
SOT-89
2
1
3
VOUT GND
(TAB)
2
GND
VIN
SOT-223
3
1
VIN VOUT
(TAB)
SOT-223 (L-Type)
2
3
GND
VOUT
VIN
TO-252
Typical Application Circuit
RT9166/A
VIN
VIN
CIN
VOUT
COUT
GND
VOUT
1uF
1uF
μF minimum X7R or X5R dielectric is strongly recommended if ceramics are
Note: To prevent oscillation, a 1μ
used as input/output capacitors. When using the Y5V dielectric, the minimum value of the input/output
μF. (see Application
capacitance that can be used for stable over full operating temperature range is 3.3μ
Information Section for further details)
Functional Pin Description
Pin Name
Pin Function
VIN
Supply Input
VOUT
Regulator Output
GND
Common Ground
Function Block Diagram
VIN
VOUT
Thermal
Shutdown
Error
Amplifier
-
+
Current
Limiting
Sensor
1.2V
Reference
GND
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RT9166/A
Absolute Maximum Ratings
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(Note 1)
Supply Input Voltage -------------------------------------------------------------------------------------------------- 6.5V
Power Dissipation, PD @ TA = 25°C
SOT-23-3 ---------------------------------------------------------------------------------------------------------------- 0.4W
SOT-89 ------------------------------------------------------------------------------------------------------------------- 0.571W
SOT-223 ----------------------------------------------------------------------------------------------------------------- 0.740W
TO-252 ------------------------------------------------------------------------------------------------------------------- 1.470W
Package Thermal Resistance (Note 4)
SOT-23-3, θJA ----------------------------------------------------------------------------------------------------------- 250°C/W
SOT-89, θJA ------------------------------------------------------------------------------------------------------------- 175°C/W
SOT-89, θJC ------------------------------------------------------------------------------------------------------------- 58°C/W
SOT-223, θJA ------------------------------------------------------------------------------------------------------------ 135°C/W
SOT-223, θJC ----------------------------------------------------------------------------------------------------------- 15°C/W
TO-252, θJA ------------------------------------------------------------------------------------------------------------- 68°C/W
TO-252, θJC ------------------------------------------------------------------------------------------------------------- 7°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
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(Note 3)
Supply Input Voltage -------------------------------------------------------------------------------------------------- 2.8V to 5.5V
Junction Temperature Range ---------------------------------------------------------------------------------------- – 40°C to 125°C
Ambient Temperature Range ---------------------------------------------------------------------------------------- – 40°C to 85°C
Electrical Characteristics
(VIN = VOUT + 1V or VIN = 2.8V whichever is greater, CIN = 1μF, COUT = 1μF, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Output Voltage Accuracy
RT9166
Current Limit
Quiescent Current
RT9166A
(Note 6)
Dropout Voltage
RT9166
(Note 7)
RT9166A
Load Regulation
RT9166
(Note 5)
RT9166A
Min
Typ
Max
Units
−1
--
+3
%
300
--
--
600
--
--
ΔVOUT
IOUT = 1mA
ILIM
RLOAD = 1Ω
IQ
IOUT = 0mA
--
220
300
IOUT = 300mA
--
230
--
IOUT = 600mA
--
580
--
--
0.2
--
1mA < IOUT < 300mA
--
15
35
1mA < IOUT < 600mA
--
30
55
f = 1kHz, COUT = 1μF
--
−55
--
dB
VDROP
ΔVLINE
Line Regulation
Test Conditions
ΔVLOAD
VIN = (VOUT + 0.3V) to 5.5V,
IOUT = 1mA
mA
μA
mV
%/V
mV
Power Supply Rejection Rate
PSRR
Thermal Shutdown Temperature
TSD
--
170
--
°C
Thermal Shutdown Hysteresis
ΔTSD
--
40
--
°C
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RT9166/A
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. θJA is measured in the natural convection at TA = 25°C on a single layer low effective thermal conductivity test board of
JEDEC 51-3 thermal measurement standard.
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 IQ = IIN - IOUT under
no load condition (IOUT = 0mA). The total current drawn from the supply is the sum of the load current plus the ground
pin current.
Note 7.The dropout voltage is defined as VIN -VOUT, which is measured when VOUT is VOUT(NORMAL) − 100mV.
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DS9166/A-18 June 2007
RT9166/A
Typical Operating Characteristics
Power Supply Rejection Ratio
Dropout Voltage vs. Load Current
700
CIN = 1uF
COUT = 1uF
600
VIN = 5V
CIN = 1uF
COUT = 1uF
TJ = 125°C
-10
500
TJ = 25°C
400
300
TJ = −40°C
200
-20
PSRR (dB)
Dropout Voltage (mV)
0
-30
100mA
-40
1mA
-50
100
-60
0
0
100
200
300
400
500
10
600
1k
10k
Load Current (mA)
Frequency (Hz)
Region of Stable COUT ESR vs. Load Current
Output Noise
100.00
Output Noise Signal (μV)
10.00
Instable
1.00
Stable
0.10
Instable
0.01
100k
1M
ILOAD = 100mA
COUT = 1uF
VIN = 5V
CIN = 1uF
COUT = 1uF to 4.7uF
COUT ESR (Ω)
100
400
200
0
-200
-400
f = 10Hz to
0.00
0
100
200
300
400
500
Time (1ms/DIV)
600
Load Current (mA)
Current Limit vs. Input voltage
900
850
850
Current Limit (mA)
Current Limit (mA)
Current Limit vs. Input voltage
900
800
VIN = 5V
CIN = 1uF
COUT = 1uF
RL = 0.5Ω
750
800
750
VIN = 5V
CIN = 1uF
COUT = 1uF
RL = 0.5Ω
RT9166-33CX
700
700
3
3.5
4
4.5
Input voltage (V)
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5
5.5
3
3.5
RT9166-33CVL
4
4.5
5
5.5
Input voltage (V)
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RT9166/A
Current Limit vs. Temperature
900
850
850
Current Limit (mA)
Current Limit (mA)
Current Limit vs. Temperature
900
800
VIN = 5V
CIN = 1uF
COUT = 1uF
RL = 0.5Ω
750
800
VIN = 5V
CIN = 1uF
COUT = 1uF
RL = 0.5Ω
750
RT9166-33CX
700
-40
-50
-25
0
25
50
75
100
125
-50
-40
Temperature (°C)
240
240
Quiescent Current (uA) 1
260
220
200
180
VIN = 5V
CIN = 1uF
COUT = 1uF
0
50
75
100
125
220
200
180
160
RT9166-33CX
VIN = 5V
CIN = 1uF
COUT = 1uF
RT9166-33CVL
140
140
-40
-50
-25
0
25
50
75
100
-50
-40
125
-25
0
Temperature (°C)
3.35
3.35
Output Voltage (V)
3.4
3.3
3.25
3.2
-40
-50
-25
RT9166-33CX
0
25
50
Temperature (°C)
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50
75
100
125
Temperature Stability
3.4
VIN = 5V
CIN = 1uF
COUT = 1uF
25
Temperature (°C)
Temperature Stability
Output Voltage (V)
25
Quiescent Current vs. Temperature
260
160
-25
Temperature (°C)
Quiescent Current vs. Temperature
Quiescent Current (uA) 1
RT9166-33CVL
700
75
100
125
3.3
3.25
VIN = 5V
CIN = 1uF
COUT = 1uF
3.2
-50
-40
-25
RT9166-33CVL
0
25
50
75
100
125
Temperature (°C)
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RT9166/A
VIN = 5V, ILOAD = 1 to 150mA
CIN = COUT = 1uF (Ceramic, X7R)
Load
Current (mA)
200
100
0
20
0
-20
Load Transient Response
RT9166-33CX
Time (100us/Div)
Output Voltage
Deviation (mV)
Output Voltage
Deviation (mV)
Load
Current (mA)
Load Transient Response
200
VIN = 5V, ILOAD = 1 to 150mA
CIN = COUT = 1uF (Ceramic, X7R)
100
0
20
0
-20
RT9166-33CVL
Time (100us/Div)
Output Voltage
Deviation (mV)
Input Voltage
Deviation (V)
Line Transient Response
5
VIN = 4 to 5V
CIN = 1uF
COUT = 1uF
4
20
0
-20
Time (100us/Div)
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RT9166/A
Application Information
Like any low-dropout regulator, the RT9166/A series
requires input and output decoupling capacitors. These
capacitors must be correctly selected for good performance
(see Capacitor Characteristics Section). Please note that
linear regulators with a low dropout voltage have high
internal loop gains which require care in guarding against
oscillation caused by insufficient decoupling capacitance.
Input-Output (Dropout) Voltage
A regulator's minimum input-to-output voltage differential
(dropout voltage) determines the lowest usable supply
voltage. In battery-powered systems, this determines the
useful end-of-life battery voltage. Because the device uses
a PMOS, its dropout voltage is a function of drain-to-source
on-resistance, RDS(ON), multiplied by the load current :
VDROPOUT = VIN - VOUT = RDS(ON) x IOUT
Input Capacitor
An input capacitance of ≅ 1μF is required between the
device input pin and ground directly (the amount of the
capacitance may be increased without limit). The input
capacitor MUST be located less than 1 cm from the device
to assure input stability (see PCB Layout Section). A lower
ESR capacitor allows the use of less capacitance, while
higher ESR type (like aluminum electrolytic) require more
capacitance.
Current Limit
The RT9166/A monitors and controls the PMOS' gate
voltage, minimum limiting the output current to 300mA for
RT9166 and 600mA for RT9166A. The output can be
shorted to ground for an indefinite period of time without
damaging the part.
Short-Circuit Protection
There are no requirements for the ESR on the input
capacitor, but tolerance and temperature coefficient must
be considered when selecting the capacitor to ensure the
capacitance will be ≅ 1μF over the entire operating
temperature range.
The device is short circuit protected and in the event of a
peak over-current condition, the short-circuit control loop
will rapidly drive the output PMOS pass element off. Once
the power pass element shuts down, the control loop will
rapidly cycle the output on and off until the average power
dissipation causes the thermal shutdown circuit to respond
to servo the on/off cycling to a lower frequency. Please
refer to the section on thermal information for power
dissipation calculations.
Output Capacitor
Capacitor Characteristics
The RT9166/A is designed specifically to work with very
small ceramic output capacitors. The recommended
minimum capacitance (temperature characteristics X7R or
X5R) is 1μF to 4.7μF range with 10mΩ to 50mΩ range
ceramic capacitor between LDO output and GND for
transient stability, but it may be increased without limit.
Higher capacitance values help to improve transient. The
output capacitor's ESR is critical because it forms a zero
to provide phase lead which is required for loop stability.
(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.)
It is important to note that capacitance tolerance and
variation with temperature must be taken into consideration
when selecting a capacitor so that the minimum required
amount of capacitance is provided over the full operating
temperature range. In general, a good tantalum capacitor
will show very little capacitance variation with temperature,
but a ceramic may not be as good (depending on dielectric
type).
Capacitor types (aluminum, ceramic and tantalum) can be
mixed in parallel, but the total equivalent input capacitance/
ESR must be defined as above to stable operation.
No Load Stability
The device will remain stable and in regulation with no
external load. This is specially important in CMOS RAM
keep-alive applications.
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Aluminum electrolytics also typically have large
temperature variation of capacitance value.
Equally important to consider is a capacitor's ESR change
with temperature: this is not an issue with ceramics, as
their ESR is extremely low. However, it is very important in
Tantalum and aluminum electrolytic capacitors. Both show
increasing ESR at colder temperatures, but the increase
DS9166/A-18 June 2007
RT9166/A
in aluminum electrolytic capacitors is so severe they may
not be feasible for some applications.
Ceramic :
For values of capacitance in the 10μF to 100μF range,
ceramics are usually larger and more costly than tantalums
but give superior AC performance for by-passing high
frequency noise because of very low ESR (typically less
than 10mΩ). However, some dielectric types do not have
good capacitance characteristics as a function of voltage
and temperature.
Z5U and Y5V dielectric ceramics have capacitance that
drops severely with applied voltage. A typical Z5U or Y5V
capacitor can lose 60% of its rated capacitance with half of
the rated voltage applied to it. The Z5U and Y5V also exhibit
a severe temperature effect, losing more than 50% of
nominal capacitance at high and low limits of the
temperature range.
X7R and X5R dielectric ceramic capacitors are strongly
recommended if ceramics are used, as they typically
maintain a capacitance range within ±20% of nominal over
full operating ratings of temperature and voltage. Of course,
they are typically larger and more costly than Z5U/Y5U
types for a given voltage and capacitance.
Tantalum :
Solid tantalum capacitors are recommended for use on
the output because their typical ESR is very close to the
ideal value required for loop compensation. They also work
well as input capacitors if selected to meet the ESR
requirements previously listed.
Tantalums also have good temperature stability: a good
quality tantalum will typically show a capacitance value
that varies less than 10~15% across the full temperature
range of 125°C to -40°C. ESR will vary only about 2X going
from the high to low temperature limits.
The increasing ESR at lower temperatures can cause
oscillations when marginal quality capacitors are used (if
the ESR of the capacitor is near the upper limit of the
stability range at room temperature).
Aluminum :
This capacitor type offers the most capacitance for the
money. The disadvantages are that they are larger in
physical size, not widely available in surface mount, and
have poor AC performance (especially at higher
frequencies) due to higher ESR and ESL.
Compared by size, the ESR of an aluminum electrolytic is
higher than either Tantalum or ceramic, and it also varies
greatly with temperature. A typical aluminum electrolytic
can exhibit an ESR increase of as much as 50X when going
from 25°C down to -40°C.
It should also be noted that many aluminum electrolytics
only specify impedance at a frequency of 120Hz, which
indicates they have poor high frequency performance. Only
aluminum electrolytics that have an impedance specified
at a higher frequency (between 20kHz and 100kHz) should
be used for the device. Derating must be applied to the
manufacturer's ESR specification, since it is typically only
valid at room temperature.
Any applications using aluminum electrolytics should be
thoroughly tested at the lowest ambient operating
temperature where ESR is maximum.
Thermal Considerations
Thermal protection limits power dissipation in RT9166/A.
When the operation junction temperature exceeds 170°C,
the OTP circuit starts the thermal shutdown function and
turns the pass element off. The pass element turn on again
after the junction temperature cools by 40°C.
For continuous operation, do not exceed absolute
maximum operation junction temperature. The power
dissipation definition in device is :
PD = (VIN - VOUT) x IOUT + VIN x IQ
The maximum power dissipation depends on the thermal
resistance of IC package, PCB layout, the rate of
surroundings airflow and temperature difference between
junction to ambient. The maximum power dissipation can
be calculated by following formula :
PD (MAX) = ( TJ(MAX) - TA ) / θJA
Where T J(MAX) is the maximum operation junction
temperature 125°C, TA is the ambient temperature and the
θJA is the junction to ambient thermal resistance.
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RT9166/A
For recommended operating conditions specification of
RT9166/A, where T J(MAX) is the maximum junction
temperature of the die (125°C) and TA is the operated
ambient temperature. The junction to ambient thermal
resistance θ JA is layout dependent. For SOT-23-3
packages, the thermal resistance θJA is 250°C/W on the
standard JEDEC 51-3 single-layer thermal test board. The
maximum power dissipation at TA = 25°C can be calculated
by following formula :
PD (MAX) = ( 125°C − 25°C) / 250°C/W = 0.400W for
SOT-23-3 packages
PD (MAX) = ( 125°C − 25°C) / 175°C/W = 0.571W for
SOT-89 packages
PD (MAX) = ( 125°C − 25°C) / 135°C/W = 0.740W for
SOT-223 packages
PD (MAX) = ( 125°C − 25°C) / 68°C/W = 1.470W for
TO-252 packages
Maximum Power Dissipation (mW)
The maximum power dissipation depends on operating
ambient temperature for fixed T J(MAX) and thermal
resistance θJA. For RT9166/A packages, Figure 1 of
derating curves allows the designer to see the effect of
rising ambient temperature on the maximum power allowed.
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
Single Layer PCB
TO-252
PCB Layout
Good board layout practices must be used or instability
can be induced because of ground loops and voltage drops.
The input and output capacitors MUST be directly
connected to the input, output, and ground pins of the
device using traces which have no other currents flowing
through them.
The best way to do this is to layout CIN and COUT near the
device with short traces to the VIN, VOUT, and ground pins.
The regulator ground pin should be connected to the
external circuit ground so that the regulator and its
capacitors have a “single point ground”.
It should be noted that stability problems have been seen
in applications where “vias” to an internal ground plane
were used at the ground points of the device and the input
and output capacitors. This was caused by varying ground
potentials at these nodes resulting from current flowing
through the ground plane. Using a single point ground
technique for the regulator and it’ s capacitors fixed the
problem. Since high current flows through the traces going
into VIN and coming from VOUT, Kelvin connect the capacitor
leads to these pins so there is no voltage drop in series
with the input and output capacitors.
Optimum performance can only be achieved when the
device is mounted on a PC board according to the diagram
below :
VIN
SOT-223
SOT-89
SOT-23-3
GND
0
25
50
75
100
Ambient Temperature (°C)
Figure 1. Derating Curves for RT9166/A Packages
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125
VOUT
Figure 2. SOT-23-3 Board Layout
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RT9166/A
Outline Dimension
H
D
L
C
B
e
A
A1
b
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.889
1.295
0.035
0.051
A1
0.000
0.152
0.000
0.006
B
1.397
1.803
0.055
0.071
b
0.356
0.508
0.014
0.020
C
2.591
2.997
0.102
0.118
D
2.692
3.099
0.106
0.122
e
1.803
2.007
0.071
0.079
H
0.080
0.254
0.003
0.010
L
0.300
0.610
0.012
0.024
SOT-23-3 Surface Mount Package
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RT9166/A
D
D1
A
B
C
C1
e
e
H
A
b
Symbol
b1
b
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
1.397
1.600
0.055
0.063
b
0.356
0.483
0.014
0.019
B
2.388
2.591
0.094
0.102
b1
0.406
0.533
0.016
0.021
C
3.937
4.242
0.155
0.167
C1
0.787
1.194
0.031
0.047
D
4.394
4.597
0.173
0.181
D1
1.397
1.753
0.055
0.069
e
1.448
1.549
0.057
0.061
H
0.356
0.432
0.014
0.017
3-Lead SOT-89 Surface Mount Package
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DS9166/A-18 June 2007
RT9166/A
D
D1
H
C
B
L
e
L1
e
A
A1
b
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
1.450
1.803
0.057
0.071
A1
0.020
0.100
0.0008
0.0047
b
0.610
0.787
0.024
0.031
B
3.302
3.708
0.130
0.146
C
6.706
7.290
0.264
0.287
D
6.299
6.706
0.248
0.264
D1
2.896
3.150
0.114
0.124
e
2.261
2.362
0.089
0.093
H
0.229
0.330
0.009
0.013
L
1.550
1.950
0.061
0.077
L1
0.800
1.100
0.009
0.013
3-Lead SOT-223 Surface Mount Package
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RT9166/A
D
U
C
D1
R
B
T
V
E
S
L1
L3
b1
b
L2
e
b2
A
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
2.184
2.388
0.086
0.094
B
0.889
2.032
0.035
0.080
b
0.508
0.889
0.020
0.035
b1
1.016 Ref.
0.040 Ref.
b2
0.457
0.584
0.018
0.023
C
0.457
0.584
0.018
0.023
D
6.350
6.731
0.250
0.265
D1
5.207
5.461
0.205
0.215
E
5.334
6.223
0.210
0.245
e
2.108
2.438
0.083
0.096
L1
9.398
10.414
0.370
0.410
L2
L3
0.508 Ref.
0.635
1.016
0.020 Ref.
0.025
0.040
U
3.810 Ref.
0.150 Ref.
V
3.048 Ref.
0.120 Ref.
R
0.200
0.850
0.008
0.033
S
2.500
3.400
0.098
0.134
T
0.500
0.850
0.020
0.033
3-Lead TO-252 Surface Mount Package
www.richtek.com
14
DS9166/A-18 June 2007
RT9166/A
A
D
E
L
b
e
C
D1
A1
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
3.175
4.191
0.125
0.165
A1
1.143
1.372
0.045
0.054
b
0.406
0.533
0.016
0.021
C
0.406
0.533
0.016
0.021
D
4.445
5.207
0.175
0.205
D1
3.429
5.029
0.135
0.198
E
4.318
5.334
0.170
0.210
e
1.143
1.397
0.045
0.055
12.700
L
0.500
3-Lead TO-92 Plastic Package
Richtek Technology Corporation
Richtek Technology Corporation
Headquarter
Taipei Office (Marketing)
5F, No. 20, Taiyuen Street, Chupei City
8F, No. 137, Lane 235, Paochiao Road, Hsintien City
Hsinchu, Taiwan, R.O.C.
Taipei County, Taiwan, R.O.C.
Tel: (8863)5526789 Fax: (8863)5526611
Tel: (8862)89191466 Fax: (8862)89191465
Email: [email protected]
DS9166/A-18 June 2007
www.richtek.com
15