®
RT9068
60V, 30μ
μA IQ, Low Dropout Voltage Linear Regulator
General Description
Features
The RT9068 family are high voltage (60V operation), low
quiescent current low dropout linear regulators capable of
supplying 50mA of output current with a maximum dropout
voltage of 300mV. The low quiescent and shutdown
currents (30μA operating and 2μA shutdown) are ideal for
use in battery-powered and/or high voltage systems.
Ground current is well-controlled in all conditions, including
dropout.
The RT9068 family operates with any reasonable output
capacitors including 1μF low-ESR ceramic types and
features excellent line and load transient responses.
Internal protection circuitry includes reverse-battery
protection, current limiting, thermal shutdown, and reverse
current protection. Output voltage accuracy is ±2% over
the entire line and load range.
These devices are available in 3 fixed-output versions
(2.5V, 3.3V, 5V) as well as a version that supports an
adjustable output voltage (1.25V to 60V). All versions
come in SOP-8 and MSOP-8 packages with an exposed
pad for high power dissipation.
Wide Input Voltage Range : 4.5V to 60V
μA
Low Quiescent Current : 30μ
μA Operating and 2μ
Shutdown
Low Dropout Voltage : 300mV maximum at 50mA
Fixed (2.5V, 3.3V, 5V) and adjustable (1.25V to 60V)
versions
±2% Output Tolerance
Stable with 1μ
μF Output Capacitor (Aluminum,
Tantalum or Ceramic)
Inherent Reverse-Current Protection (No diode
needed)
−60V Reverse-Battery Protection
Applications
Low Current, High Voltage Regulators
Battery Powered Applications
Telecom and Datacom Applications
Automotive Application
Typical Application Circuit
VOUT
2.5V/3.3V/5V
VIN
4.5V to 60V
VIN
4.5V to 60V
RT9068
CIN
0.18µF
VIN
COUT
1µF
SHDN
GND
RT9068-25/33/50
CIN
0.18µF
VIN
SENSE
GND
November 2016
R1
COUT
1µF
FB
CIN
0.18µF
VIN
VOUT
SENSE
SHDN
R2
GND
RT9068 (Adjustable Up to 25V Output)
Copyright © 2016 Richtek Technology Corporation. All rights reserved.
DS9068-05
RT9068
VOUT
SHDN
VOUT
1.25V to 60V
VIN
4.5V to 60V
RT9068
VOUT
SENSE
VOUT
1.25V to 25V
CCOMP
R1
FB
COUT
1µF
R2
RT9068 (Adjustable Up to 60V Output)
is a registered trademark of Richtek Technology Corporation.
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1
RT9068
Ordering and Marking Information
Part No.
RT906825GFP
RT906825GSP
RT906833GFP
RT906833GSP
RT906850GFP
RT906850GSP
RT9068
GFP
RT9068
GSP
Output
Voltage
Package
MSOP-8
Marking
Information
09=
2.5V
SOP-8
RT906825GSP
MSOP-8
0A=
SOP-8
RT906833GSP
MSOP-8
0B=
(TOP VIEW)
VOUT
SENSE
NC
NC
5V
SOP-8
3
4
GND
7
9 6
5
MSOP-8
VOUT
SENSE
FB
NC
VIN
GND
GND
SHDN
8
2
3
4
GND
7
9 6
5
RT906850GSP
RT9068
MSOP-8
08=
SOP-8
RT9068GSP
MSOP-8
Adjustable
Richtek products are :
VOUT
8
SENSE
2
NC
3
NC
4
GND
9
VIN
7
GND
6
GND
5
SHDN
RoHS compliant and compatible with the current requireRT9068-25/33/50
ments of IPC/JEDEC J-STD-020.
VIN
GND
GND
SHDN
8
2
RT9068-25/33/50
3.3V
Note :
Pin Configurations
SOP-8
Suitable for use in SnPb or Pb-free soldering processes.
VOUT
8
SENSE
2
FB
3
NC
4
GND
9
VIN
7
GND
6
GND
5
SHDN
RT9068
SOP-8
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is a registered trademark of Richtek Technology Corporation.
DS9068-05
November 2016
RT9068
Pin Description
Pin No.
RT9068RT9068GSP/GFP
25/33/50GSP/GFP
1
1
Name
Function
VOUT
VOUT supplies power to the load. A minimum output
capacitor of 1F is required for stable operation.
Output Voltage Sense. For applications with VOUT 25V,
SENSE can be connected to the output voltage to optimize
the control loop compensation.
For applications with VOUT > 25V (adjustable versions only),
SENSE must be left unconnected. Control loop compensation
is optimized by adding a feed-forward capacitor in the
feedback resistor divider connected to FB (see Adjustable
Output Voltage and Compensation section).
2
2
SENSE
3
--
NC
No Internal Connection.
--
3
FB
Feedback Input. Connect to the center tap of a resistor divider
for setting the output voltage. (Adjustable versions only)
4
--
NC
No Internal Connection.
5
5
SHDN
Shutdown Control Input (Active High). Connect SHDN high to
disable the output voltage and reduce the IC’s quiescent
current to 2A (typical). Connect SHDN low to enable the
output. SHDN is a high-voltage input (also able to withstand
reverse voltage) and can be connected directly to a
high-voltage input.
6, 7, 9*
6, 7, 9*
GND
Ground. The exposed pad should be soldered to a large PCB
and connected to GND for maximum thermal dissipation.
8
8
VIN
Power Input. Bypass VIN with a 0.18F or larger capacitor
with adequate voltage rating.
* exposed pad
Function Block Diagram
VOUT
VIN
Current Limit
Error Amp
VOUT
VIN
Current Limit
Error Amp
SHDN
SHDN
OverTemperature
Protection
SENSE
-
+
+
-
OverTemperature
Protection
SENSE
FB
Reference
Reference
GND
RT9068-25/33/50 (Fixed Output)
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DS9068-05
November 2016
GND
RT9068 (Adjustable Output)
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RT9068
Operation
The RT9068 is a high input-voltage linear regulator
specifically designed to minimize external components.
The input voltage range is from 4.5V to 60V. The device
supplies 50mA of output current with a maximum dropout
voltage of 300mV. Its 30μA quiescent and 2μA shutdown
currents make it ideal for use in battery-powered
applications. Unlike many PNP LDO regulators, ground
current does not increase much in dropout conditions.
Output Transistor
The RT9068 includes a built-in PNP output transistor
configured for low dropout voltage. The output transistor
blocks reverse current if the output voltage is held higher
than the input voltage (such as in battery-backup
applications) so no additional output blocking diode is
needed.
Over-Temperature Protection
The over temperature protection function will turn off the
PNP output transistor when the internal junction
temperature exceeds 155°C (typ.). Once the junction
temperature cools down by approximately 5°C, the
regulator will automatically resume operation.
Reverse-Battery Protection
The RT9068 inputs (VIN and SHDN) can withstand reverse
voltages as high as −60V. Both the IC and the load are
protected, as long as the load impedance is 500Ω or less.
In these conditions, the output voltage is guaranteed to
be no more negative than −1V with the maximum negative
input voltage. In battery-powered applications, no
additional protection against battery reversal is typically
needed.
Error Amplifier
Reverse-Output Protection
The Error Amplifier compares the output feedback voltage
from an internal feedback voltage divider (fixed output
versions) or FB (adjustable output versions) to an internal
reference voltage and controls the PNP output transistor's
base current to maintain output voltage regulation. The
RT9068's internal dividers are placed between SENSE and
GND and have a divider resistance of about 1MΩ.
The RT9068 protects against current flow to the input (VIN)
when the output voltage exceeds VIN. This simplifies
battery and capacitive “keep-alive” circuits since they
need no additional output blocking diode.
Current Limit Protection
The RT9068 provides a current limit function to prevent
damage during output over-load or shorted-circuit
conditions. The output current is detected by an internal
current-sense transistor.
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Shutdown Input (8 Pin Versions)
The RT9068 SHDN input is an active-high input that turns
off the output transistor and reduces the quiescent current
to 2μA typical. Connect SHDN to a voltage below 0.6V for
normal operation.
is a registered trademark of Richtek Technology Corporation.
DS9068-05
November 2016
RT9068
Absolute Maximum Ratings
(Note 1)
VIN to GND ------------------------------------------------------------------------------------------------------------------SHDN to GND --------------------------------------------------------------------------------------------------------------VOUT to GND --------------------------------------------------------------------------------------------------------------SENSE to GND ------------------------------------------------------------------------------------------------------------VIN to VOUT/SENSE when |VIN| ≥ |VOUT| (Normal Operation or Reverse-Battery Condition) -------VIN to VOUT/SENSE when VOUT ≥ VIN ≥ 0 (Reverse-VOUT Condition) -----------------------------------FB -----------------------------------------------------------------------------------------------------------------------------FB Current ------------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C
MSOP-8 ---------------------------------------------------------------------------------------------------------------------SOP-8 ------------------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2)
MSOP-8, θJA ----------------------------------------------------------------------------------------------------------------MSOP-8, θJC ---------------------------------------------------------------------------------------------------------------SOP-8, θJA ------------------------------------------------------------------------------------------------------------------SOP-8, θJC ------------------------------------------------------------------------------------------------------------------Junction Temperature -----------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------------Storage Temperature Range --------------------------------------------------------------------------------------------ESD Susceptibility (Note 3)
HBM (Human Body Model) -----------------------------------------------------------------------------------------------
Recommended Operating Conditions
−60V to 80V
−60V to 80V
−40V to 80V
−30V to 35V
−60V to 80V
−35V
−0.3V to 10V
−6mA to 6mA
2.1W
3.26W
47.4°C/W
11.9°C/W
30.6°C/W
3.4°C/W
150°C
260°C
−65°C to 150°C
2kV
(Note 4)
Supply Input Voltage ------------------------------------------------------------------------------------------------------- 4.5V to 60V
Junction Temperature Range --------------------------------------------------------------------------------------------- −40°C to 125°C
Ambient Temperature Range --------------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(4.5V < VIN < 60V, VSHDN = 0V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
4.5
--
60
V
Input Supply
Operational VIN
VIN
0 < IOUT < 50mA
Quiescent Current
IQ
VIN = 24V, VSHDN = 0V
--
30
40
A
Shutdown Current
ISHDN
VIN = 24V, VSHDN = 2.5V, VOUT = 0
--
2
15
A
Input Reverse Leakage
Current
IVINr
VIN = 60V, VOUT = 0V
--
--
0.1
mA
120
--
300
mA
Output Voltage and Current
Output Current Limit
ILIM
Line Regulation
VLINE
5.5V < VIN < 60V, IOUT = 50mA
--
0.5
--
%
Load Regulation
VLOAD
0.1mA < IOUT < 50mA
--
0.7
--
%
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November 2016
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RT9068
Parameter
Min
Typ
Max
Unit
0 < IOUT < 50mA
1.225
1.25
1.275
V
0 < IOUT < 50mA
2.45
2.5
2.55
0 < IOUT < 50mA
3.24
3.3
3.36
5.4V < VIN < 60V, 0 < IOUT < 50mA
4.9
5
5.1
--
20
50
nA
VIN = 60V, RL = 500
--
--
1
V
IOUT = 1mA
--
15
80
IOUT = 10mA
--
55
150
IOUT = 50mA
--
150
300
Power Supply Rejection Rate PSRR
f = 1kHz, IOUT = 50mA
--
60
--
dB
Output Noise Voltage
VON
IOUT = 50mA, f = 10Hz to 100kHz
--
200
--
VRMS
Shutdown Output Voltage
VOUTSD
SHDN = VIN
--
--
100
mV
SHDN High Threshold
VIH
--
1.6
2.2
V
SHDN Low Threshold
VIL
0.6
1.2
--
V
SHDN Input Bias Current
ISHDN
SHDN = VIN
--
0.6
1.2
VSHDN = 0V
--
--
0.1
145
155
165
FB Regulation
Voltage
RT9068
Symbol
VFB
RT9068-25
Output Voltage RT9068-33
VOUT
RT9068-50
FB Input Bias
Current
RT9068
IFB
Output Voltage with Reverse
VROUT
Polarity VIN
Dropout Voltage
Test Conditions
VDROP
V
mV
Shutdown
A
Thermal Protection
Thermal Shutdown
TSD
C
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. θJC is
measured at the exposed pad of the package.
Note 3. Devices are ESD sensitive. Handling precaution is recommended.
Note 4. The device is not guaranteed to function outside its operating conditions.
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is a registered trademark of Richtek Technology Corporation.
DS9068-05
November 2016
RT9068
Typical Operating Characteristics
(TA = 25°C, CIN = 0.18μF, COUT = 1μF, unless otherwise specified)
Output Voltage vs. Output Current
Quiescent Current vs. Input Voltage
35
0.0
Quiescent Current (μA)
Output Voltage (%) 1
30
-0.2
-0.4
-0.6
-0.8
SHDN_Low
25
20
15
10
SHDN_High
5
VIN = 4.5V to 60V
VIN = 14V
-1.0
0
10
20
30
40
0
0
50
10
20
Output Current (mA)
30
40
50
60
Input Voltage (V)
Output Voltage vs. Temperature
Quiescent Current vs. Temperature
45
3.4
VIN = 14V
Output Voltage (V)
3.4
Quiescent Current (μA)
40
IOUT = 1mA
3.3
IOUT = 10mA
3.3
3.2
3.2
VIN = 14V
-25
0
25
50
75
100
30
SHDN_Low
25
20
15
10
SHDN_High
5
0
3.1
-50
35
-50
125
-25
0
Temperature(°C)
SHDN Threshold Voltage (V)
PSRR/dB
-20
COUT = 1μF
-30
-40
-50
COUT = 10μF
-70
IOUT = 50mA
-80
10
100
1000
10000
100000
Frequency (Hz)
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DS9068-05
November 2016
75
100
125
2.5
-10
-60
50
SHDN Threshold Voltage vs. Temperature
PSRR
0
25
Temperature (°C)
1000000
2.0
VIH
1.5
VIL
1.0
0.5
VIN = 14V
0.0
-50
-25
0
25
50
75
100
125
150
Temperature (°C)
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RT9068
Output Voltage vs. Input Voltage
Current Limit vs. Input Voltage
3.40
210
Output Voltage (V) 1
Current Limit (mA)
3.38
TA = 125°C
190
170
TA = −40°C
150
130
110
90
3.36
3.34
3.32
3.30
IOUT = 0mA IOUT = 40mA
IOUT = 1mA IOUT = 50mA
IOUT = 5mA
IOUT = 10mA
IOUT = 20mA
IOUT = 30mA
3.28
3.26
3.24
3.22
70
3.20
0
10
20
30
40
50
60
0
10
20
3.0
0.25
2.5
In Dropout
1.5
2V Dropout
1.0
0.10
0.0
0.00
SHDN = VIN, VOUT = SENSE = GND
0
10
20
30
40
50
-80
Output Current (mA)
-70
-60
-50
-40
-30
-20
-10
0
Reverse Voltage (V)
Dropout Voltage vs. Temperature
Output Noise vs. Frequency
200
250
IOUT = 0mA IOUT = 40mA
IOUT = 1mA IOUT = 50mA
IOUT = 10mA
IOUT = 20mA
IOUT = 30mA
180
Output Noise (µV)
Dropout Voltage (mV)
60
0.15
0.05
150
50
0.20
0.5
200
40
Leakage Current vs. Reverse Voltage
0.30
Leakage Current (mA)1
Ground Current (mA)
Ground Current vs. Output Current
3.5
2.0
30
Input Voltage (V)
Input Voltage (V)
100
160
140
50
120
0
100
VIN = 12V, IOUT = 10mA
-50
-25
0
25
50
75
100
Temperature (°C)
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125
10
100
1000
10000
100000
Frequency (Hz)
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DS9068-05
November 2016
RT9068
VOUT vs. VIN
Minimum Input Voltage vs. Temperature
Minimum Input Voltage (V)
3.5
3.0
IOUT = 50mA
IOUT = 10mA
2.5
VIN
(50V/Div)
2.0
1.5
1.0
VOUT
(2V/Div)
0.5
IOUT = 50mA
0.0
-50
-25
0
25
50
75
100
125
Time (1ms/Div)
Temperature (°C)
Line Transient Response
Load Transient Response
VIN = 14V, VOUT = 3.3V,
IOUT = 1mA to 50mA to 1mA
VOUT_ac
(50mV/Div)
VIN
(10V/Div)
VOUT_ac
(100mV/Div)
IOUT
(20mA/Div)
IOUT = 20mA
Time (25μs/Div)
Time (25μs/Div)
Load Transient Response
Load Transient Response
VIN = 14V, VOUT = 3.3V
VIN = 14V, VOUT = 3.3V
VOUT_ac
(20mV/Div)
VOUT_ac
(50mV/Div)
IOUT
(20mA/Div)
IOUT
(20mA/Div)
IOUT = 10mA to 40mA to 10mA
Time (10μs/Div)
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November 2016
IOUT = 10mA to 60mA to 10mA
Time (10μs/Div)
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RT9068
Turn-On by SHDN at No Load
Power-On at No Load
VIN
(50V/Div)
VOUT
(1V/Div)
SHDN
(2V/Div)
VIN = 60V, VOUT = 3.3V,
IOUT = 0mA
VOUT
(1V/Div)
IOUT
(50mA/Div)
IOUT
(50mA/Div)
Time (50μs/Div)
Time (500μs/Div)
Power-On at 50mA Load
Turn-On by SHDN at 50mA Load
VIN
(50V/Div)
SHDN
(2V/Div)
VOUT
(1V/Div)
VOUT
(1V/Div)
IOUT
(50mA/Div)
VIN = 60V, VOUT = 3.3V,
IOUT = 50mA
Time (50μs/Div)
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VIN = 60V, VOUT = 3.3V,
IOUT = 0mA
IOUT
(50mA/Div)
VIN = 60V, VOUT = 3.3V,
IOUT = 50mA
Time (500μs/Div)
is a registered trademark of Richtek Technology Corporation.
DS9068-05
November 2016
RT9068
Applications Information
The RT9068 is a high input-voltage linear regulator
specifically designed to minimize external components.
The input voltage range is from 4.5V to 60V. The device
supplies 50mA of output current with a maximum dropout
voltage of 300mV.
The fixed output versions are equipped with internal
resistive dividers to set the output voltage to 2.5V, 3.3V,
or 5V, respectively. The total resistance of the each internal
feedback divider is about 1MΩ The internal dividers connect
between SENSE and GND, with the midpoint connecting
to the input of the error amplifier. These versions are all
internally compensated.
Adjustable Output Voltage and Compensation
RT9068
The adjustable output versions may be set to provide from
1.25V to 60V, using external feedback voltage divider
resistors (Figure 1). These included an internal feedforward compensation capacitor, connected between
SENSE and FB, which may be used when regulating at
output voltages up to 25V. To achieve the correct
compensation (together with your external FB divider, use
an upper divider resistor (R1) value between 500kΩ and
1MΩ. Calculate R2 according to the following formula :
R2 = R1 / (VOUT / 1.25V − 1).
For output voltages greater than 25V an external feedforward capacitor (Figure 2) should be used and SENSE
should be left unconnected. Choose a lower divider resistor
(R2) at least 10kΩ and calculate R1 according to the
following formula : R1 = R2 x (VOUT / 1.25V − 1), Then,
calculate the compensation capacitor (CCOMP) value
according to the following formula : CCOMP = 25μs / R1.
RT9068
CIN
0.18µF
VIN
RT9068
CIN
0.18µF
VIN
VOUT
SENSE
CCOMP
R1
COUT
1µF
VOUT
1.25V to 60V
FB
SHDN
R2
GND
Figure 2. RT9068 Adjustable Output Above 25V
Fixed VOUT Applications
VIN
4.5V to 60V
VIN
4.5V to 60V
VOUT
SENSE
SHDN
GND
R1
COUT
1µF
VOUT
1.25V to 25V
Remote-Sense Applications
Since VOUT and SENSE (and FB) are separate pins, it is
possible to connect SENSE to the output voltage remotely
at the load (as long as the output voltage is 25V or less).
FB can also be connected remotely, with SENSE
unconnected if the output exceeds 25V. Remote sensing
eliminates output voltage errors due to any resistive voltage
drop between VOUT and the load. (Voltage drops in the
ground connection cannot be compensated.)
Added External NPN for High-Current Applications
Higher output currents and/or increased power dissipation
are possible using an external NPN output transistor. VOUT
drives the base of the transistor and SENSE and/or FB
monitors the actual output voltage, as in normal
applications. The fixed-output versions (Figure 3) or
adjustable-output version (Figure 4) can be used.
Figure 3 and Figure 4 have no current limit and should be
used with care. If a crude current limit is desired, add the
two diodes and resistor shown in Figure 5. The approximate
current limit is 0.7V/R3. Any small switching diodes can
be used and size R3 for the power dissipated in R3, which
is typically 0.7V x 0.7V / R3.
VIN
4.5V to 60V
RT9068
CIN
0.18µF
VIN
MJD31C
VOUT
100
SHDN SENSE
GND
COUT
10µF
VOUT
2.5V/3.3V/5V
FB
R2
Figure 3. RT9068-25/33/50 External Transistor
Application
Figure 1. RT9068 Adjustable Output Up to 25V
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RT9068
PD(MAX) = (TJ(MAX) − TA) / θJA
CIN
0.18µF
VOUT
VIN
100
CCOMP
SENSE
SHDN
VOUT
1.25V to 60V
COUT
10µF
R1
FB
GND
R2
Figure 4. RT9068 External Transistor Application
VIN
4.5V to 60V
RT9068
CIN
0.18µF
VIN
MJD31C
VOUT
100
SHDN
SENSE
GND
1N4148 x 2
R3
COUT
10µF
VOUT
2.5V/3.3V/5V
Figure 5. RT9068 External Transistor Application
with Current Limit
Component Selection
A low-ESR capacitor such as ceramic type must be
connected between VIN and GND with short, wide traces
to bypass input noise. RT9068 is designed to work with
small input capacitor to reduce the cost from high-voltage
low-ESR requirement. To guarantee a minimum 0.1μF input
capacitance, a ceramic 0.18μF input capacitor with an
appropriate voltage rating is recommended.
The RT9068 operates with any reasonable output capacitor
including low-ESR ceramic types. Low-ESR aluminum and
tantalum capacitor may also be used. A minimum of 1μF
is recommended and much higher values are also
acceptable. Connect the output capacitor between VOUT
and GND with short, wide traces to keep the circuit stable.
Thermal Considerations
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 :
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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. The junction to
ambient thermal resistance, θJA, is layout dependent. For
MSOP-8 (Exposed Pad) package, the thermal resistance,
θJA, is 47.4°C/W on a standard JEDEC 51-7 four-layer
thermal test board. For SOP-8 (Exposed Pad) package,
the thermal resistance, θJA, is 30.6°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 formulas :
PD(MAX) = (125°C − 25°C) / (47.4°C/W) = 2.1W for
MSOP-8 (Exposed Pad) package
PD(MAX) = (125°C − 25°C) / (30.6°C/W) = 3.26W for
SOP-8 (Exposed Pad) package
The maximum power dissipation depends on operating
ambient temperature for fixed T J(MAX) and thermal
resistance, θJA. The derating curves in Figure 6 allow the
designer to see the effect of rising ambient temperature
on the maximum power dissipation.
4.0
Maximum Power Dissipation (W)1
VIN
4.5V to 60V
RT9068
3.5
Four-Layer PCB
SOP-8 (Exposed Pad)
3.0
2.5
2.0
MSOP-8
(Exposed Pad)
1.5
1.0
0.5
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 6. Derating Curve of Maximum Power Dissipation
is a registered trademark of Richtek Technology Corporation.
DS9068-05
November 2016
RT9068
Layout Consideration
VOUT
COUT
VOUT
SENSE
2
NC
3
NC
4
GND
9
8
VIN
7
GND
VIN
CIN
6
GND
GND
5
SHDN
Figure 7. PCB Layout Guide
Copyright © 2016 Richtek Technology Corporation. All rights reserved.
DS9068-05
November 2016
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
13
RT9068
Outline Dimension
D
L
EXPOSED THERMAL PAD
(Bottom of Package)
U
E
V
E1
e
A2
A
A1
b
Dimensions In Millimeters
Dimensions In Inches
Symbol
Min
Max
Min
Max
A
0.810
1.100
0.032
0.043
A1
0.000
0.150
0.000
0.006
A2
0.750
0.950
0.030
0.037
b
0.220
0.380
0.009
0.015
D
2.900
3.100
0.114
0.122
e
0.650
0.026
E
4.800
5.000
0.189
0.197
E1
2.900
3.100
0.114
0.122
L
0.400
0.800
0.016
0.031
U
1.300
1.700
0.051
0.067
V
1.500
1.900
0.059
0.075
8-Lead MSOP (Exposed Pad) Plastic Package
Copyright © 2016 Richtek Technology Corporation. All rights reserved.
www.richtek.com
14
is a registered trademark of Richtek Technology Corporation.
DS9068-05
November 2016
RT9068
H
A
M
EXPOSED THERMAL PAD
(Bottom of Package)
Y
J
X
B
F
C
I
D
Dimensions In Millimeters
Dimensions In Inches
Symbol
Min
Max
Min
Max
A
4.801
5.004
0.189
0.197
B
3.810
4.000
0.150
0.157
C
1.346
1.753
0.053
0.069
D
0.330
0.510
0.013
0.020
F
1.194
1.346
0.047
0.053
H
0.170
0.254
0.007
0.010
I
0.000
0.152
0.000
0.006
J
5.791
6.200
0.228
0.244
M
0.406
1.270
0.016
0.050
X
2.000
2.300
0.079
0.091
Y
2.000
2.300
0.079
0.091
X
2.100
2.500
0.083
0.098
Y
3.000
3.500
0.118
0.138
Option 1
Option 2
8-Lead SOP (Exposed Pad) Plastic 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.
DS9068-05
November 2016
www.richtek.com
15
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