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RT9068 Datasheet

Richtek USA Inc.

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Datasheet

RT9068
®
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60V, 30μμ
μμ
μA IQ, Low Dropout Voltage Linear Regulator
General Description
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.
Features
Wide Input Voltage Range : 4.5V to 60V
Low Quiescent Current : 30μμ
μμ
μA Operating and 2μμ
μμ
μA
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 1μμ
μμ
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
RT9068 (Adjustable Up to 25V Output)RT9068-25/33/50 RT9068 (Adjustable Up to 60V Output)
Typical Application Circuit
VIN
GND
VOUT
RT9068
VIN VOUT
4.5V to 60V
CIN
0.18µF
SHDN
COUT
1µF
SENSE
2.5V/3.3V/5V
VIN
GND
VOUT
RT9068
VIN VOUT
4.5V to 60V
CIN
0.18µF
SHDN
COUT
1µF
SENSE
1.25V to 25V
R1
R2
FB
VIN
GND
VOUT
RT9068
VIN VOUT
4.5V to 60V
CIN
0.18µF
SHDN
COUT
1µF
SENSE
1.25V to 60V
R1
R2
FB
CCOMP
RT9068
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Pin Configuration
Part No. Output
Voltage Package Marking
Information
RT9068-
25GFP 2.5V
MSOP-8 09=
RT9068-
25GSP
SOP-8 Exposed
Pad–Option 1) RT906825GSP
RT9068-
33GFP 3.3V
MSOP-8 0A=
RT9068-
33GSP
SOP-8 Exposed
Pad–Option 1) RT906833GSP
RT9068-
50GFP 5V
MSOP-8 0B=
RT9068-
50GSP
SOP-8 Exposed
Pad–Option 1) RT906850GSP
RT9068
GFP Adjustable
MSOP-8 08=
RT9068
GSP
SOP-8 Exposed
Pad–Option 1) RT9068GSP
Ordering and Marking Information
RT9068-25/33/50
MSOP-8
VOUT VIN
GND
GND
SHDN
NC
SENSE
NC
5
6
7
8
4
3
2GND
9
VOUT VIN
GND
GND
SHDN
NC
SENSE
FB
5
6
7
8
4
3
2GND
9
RT9068
MSOP-8
VOUT
SENSE
NC
NC
VIN
GND
SHDN
GND
GND
2
3
45
6
7
8
9
RT9068-25/33/50
SOP-8
VOUT
SENSE
FB
NC
VIN
GND
SHDN
GND
GND
2
3
45
6
7
8
9
RT9068
SOP-8
Note :
Richtek products are :
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
(TOP VIEW)
RT9068
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Pin Description
Pin No. Name Function
RT9068-
25/33/50GSP/GFP RT9068GSP/GFP
1 1 VOUT
VOUT supplies power to the load. A minimum output
capacitor of 1F is required for stable operation.
2 2 SENSE
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).
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
Functional Block Diagram
RT9068-25/33/50 (Fixed Output) RT9068 (Adjustable Output)
Current Limit
Over-
Temperature
Protection
+
-
VIN VOUT
SENSE
GND
Reference
SHDN
Error Amp
+
-
VIN VOUT
SENSE
GND
Reference
SHDN
Error Amp
FB
Current Limit
Over-
Temperature
Protection
RT9068
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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.
Error Amplifier
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.
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.
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.
Reverse-Output Protection
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.
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.
RT9068
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Electrical Characteristics
Parameter Symbol Test Conditions Min Typ Max Unit
Input Supply
Operational VIN VIN 0 < IOUT < 50mA 4.5 -- 60 V
Quiescent Current IQ V
IN = 24V, VSHDN = 0V -- 30 40 A
Shutdown Current ISHDN V
IN = 24V, VSHDN = 2.5V, VOUT = 0 -- 2 15 A
Input Reverse Leakage
Current IVINr V
IN = 60V, VOUT = 0V -- -- 0.1 mA
Output Voltage and Current
Output Current Limit ILIM 120 -- 300 mA
Line Regulation VLINE 5.5V < VIN < 60V, IOUT = 50mA -- 0.5 -- %
Load Regulation VLOAD 0.1mA < IOUT < 50mA -- 0.7 -- %
Absolute Maximum Ratings (Note 1)
VIN to GND ------------------------------------------------------------------------------------------------------------------- 60V to 80V
SHDN to GND --------------------------------------------------------------------------------------------------------------- 60V to 80V
VOUT to GND --------------------------------------------------------------------------------------------------------------- 40V to 80V
SENSE to GND ------------------------------------------------------------------------------------------------------------- 30V to 35V
VIN to VOUT/SENSE when |VIN| |VOUT| (Normal Operation or Reverse-Battery Condition) -------- 60V to 80V
VIN to VOUT/SENSE when VOUT VIN 0 (Reverse-VOUT Condition) ------------------------------------ 35V
FB ------------------------------------------------------------------------------------------------------------------------------0.3V to 10V
FB Current ------------------------------------------------------------------------------------------------------------------- 6mA to 6mA
Power Dissipation, PD @ TA = 25°C
MSOP-8 ---------------------------------------------------------------------------------------------------------------------- 2.1W
SOP-8 ------------------------------------------------------------------------------------------------------------------------- 3.26W
Package Thermal Resistance (Note 2)
MSOP-8, θJA ----------------------------------------------------------------------------------------------------------------- 47.4°C/W
MSOP-8, θJC ---------------------------------------------------------------------------------------------------------------- 11.9°C/W
SOP-8, θJA ------------------------------------------------------------------------------------------------------------------- 30.6°C/W
SOP-8, θJC ------------------------------------------------------------------------------------------------------------------- 3.4°C/W
Junction Temperature ------------------------------------------------------------------------------------------------------ 150°C
Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------------- 260°C
Storage Temperature Range --------------------------------------------------------------------------------------------- 65°C to 150°C
ESD Susceptibility (Note 3)
HBM (Human Body Model) ----------------------------------------------------------------------------------------------- 2kV
Recommended Operating Conditions (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
(4.5V < VIN < 60V, VSHDN = 0V, TA = 25°C, unless otherwise specified)
RT9068
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Parameter Symbol Test Conditions Min Typ Max Unit
FB Regulation
Voltage RT9068 VFB 0 < IOUT < 50mA 1.225 1.25 1.275 V
Output Voltage
RT9068-25
VOUT
0 < IOUT < 50mA 2.45 2.5 2.55
V
RT9068-33 0 < IOUT < 50mA 3.24 3.3 3.36
RT9068-50 5.4V < VIN < 60V, 0 < IOUT < 50mA 4.9 5 5.1
FB Input Bias
Current RT9068 IFB -- 20 100 nA
Output Voltage with Reverse
Polarity VIN VROUT V
IN = 60V, RL = 500 -- -- 1 V
Dropout Voltage VDROP
IOUT = 1mA -- 15 80
mV
IOUT = 10mA -- 55 150
IOUT = 50mA -- 150 300
Power Supply Rejection Rate PSRR f = 1kHz, IOUT = 50mA -- 60 -- dB
Output Noise Voltage VON I
OUT = 50mA, f = 10Hz to 100kHz -- 200 -- VRMS
Shutdown
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
A
VSHDN = 0V -- -- 0.1
Thermal Protection
Thermal Shutdown TSD 145 155 165 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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Typical Operating Characteristics
PSRR
-80
-70
-60
-50
-40
-30
-20
-10
0
10 100 1000 10000 100000 1000000
Frequency (Hz)
PSRR/dB
IOUT = 50mA
COUT = 1μF
COUT = 10μF
(TA = 25°C, CIN = 0.18μF, COUT = 1μF, unless otherwise specified)
SHDN Threshold Voltage vs. Temperature
0.0
0.5
1.0
1.5
2.0
2.5
-50 -25 0 25 50 75 100 125 150
Temperature (°C)
SHDN Threshold Voltage (V
)
VIN = 14V
VIH
VIL
Quiescent Current vs. Temperature
0
5
10
15
20
25
30
35
40
45
-50 -25 0 25 50 75 100 125
Temperature (°C)
Quiescent Current (μA
)
SHDN_High
SHDN_Low
VIN = 14V
Output Voltage vs. Temperature
3.1
3.2
3.2
3.3
3.3
3.4
3.4
-50 -25 0 25 50 75 100 125
Temperature(°C)
Output Voltage (V)
IOUT = 10mA
VIN = 14V
IOUT = 1mA
Quiescent Current vs. Input Voltage
0
5
10
15
20
25
30
35
0 102030405060
Input Voltage (V)
Quiescent Current (μA
)
SHDN_High
SHDN_Low
VIN = 4.5V to 60V
Output Voltage vs. Output Current
-1.0
-0.8
-0.6
-0.4
-0.2
0.0
0 1020304050
Output Current (mA)
Output Voltage (%) 1
VIN = 14V
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Leakage Current vs. Reverse Voltage
0.00
0.05
0.10
0.15
0.20
0.25
0.30
-80 -70 -60 -50 -40 -30 -20 -10 0
Reverse Voltage (V)
Leakage Current (mA) 1
SHDN = VIN, VOUT = SENSE = GND
Output Noise vs. Frequency
100
120
140
160
180
200
10 100 1000 10000 100000
Frequency (Hz)
Output Noise (µV)
VIN = 12V, IOUT = 10mA
Ground Current vs. Output Current
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0 1020304050
Output Current (mA)
Ground Current (mA
)
In Dropout
2V Dropout
Current Limit vs. Input Voltage
70
90
110
130
150
170
190
210
0 102030405060
Input Voltage (V)
Current Limit (mA)
TA = 125°C
TA = 40°C
Dropout Voltage vs. Temperature
0
50
100
150
200
250
-50 -25 0 25 50 75 100 125
Temperature (°C)
Dropout Voltage (mV)
IOUT = 0mA
IOUT = 1mA
IOUT = 10mA
IOUT = 20mA
IOUT = 30mA
IOUT = 40mA
IOUT = 50mA
Output Voltage vs. Input Voltage
3.20
3.22
3.24
3.26
3.28
3.30
3.32
3.34
3.36
3.38
3.40
0 102030405060
Input Voltage (V)
Output Voltage (V) 1
IOUT = 0mA
IOUT = 1mA
IOUT = 5mA
IOUT = 10mA
IOUT = 20mA
IOUT = 30mA
IOUT = 40mA
IOUT = 50mA
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VOUT vs. VIN
Time (1ms/Div)
VOUT
(2V/Div)
VIN
(50V/Div)
IOUT = 50mA
Load Transient Response
Time (10μs/Div)
VOUT_ac
(50mV/Div)
VIN = 14V, VOUT = 3.3V
IOUT
(20mA/Div) IOUT = 10mA to 60mA to 10mA
Load Transient Response
Time (10μs/Div)
VOUT_ac
(20mV/Div)
VIN = 14V, VOUT = 3.3V
IOUT
(20mA/Div) IOUT = 10mA to 40mA to 10mA
Line Transient Response
Time (25μs/Div)
VOUT_ac
(100mV/Div)
VIN
(10V/Div)
IOUT = 20mA
Load Transient Response
Time (25μs/Div)
VOUT_ac
(50mV/Div)
IOUT
(20mA/Div)
VIN = 14V, VOUT = 3.3V,
IOUT = 1mA to 50mA to 1mA
Minimum Input Voltage vs. Temperature
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
-50 -25 0 25 50 75 100 125
Temperature (°C)
Minimum Input Voltage (V
)
IOUT = 50mA
IOUT = 10mA
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Turn-On by SHDN at 50mA Load
Time (500μs/Div)
VOUT
(1V/Div)
IOUT
(50mA/Div)
VIN = 60V, VOUT = 3.3V,
IOUT = 50mA
SHDN
(2V/Div)
Power-On at 50mA Load
Time (50μs/Div)
VOUT
(1V/Div)
IOUT
(50mA/Div)
VIN = 60V, VOUT = 3.3V,
IOUT = 50mA
VIN
(50V/Div)
Power-On at No Load
Time (50μs/Div)
VOUT
(1V/Div)
IOUT
(50mA/Div)
VIN = 60V, VOUT = 3.3V,
IOUT = 0mA
VIN
(50V/Div)
Turn-On by SHDN at No Load
Time (500μs/Div)
VOUT
(1V/Div)
IOUT
(50mA/Div)
VIN = 60V, VOUT = 3.3V,
IOUT = 0mA
SHDN
(2V/Div)
RT9068
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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.
Fixed VOUT Applications
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 feed-
forward 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 / 1.23V 1).
For output voltages greater than 25V an external feed-
forward 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 / 1.23V 1), Then,
calculate the compensation capacitor (CCOMP) value
according to the following formula : CCOMP = 25μs / R1.
Figure 1. RT9068 Adjustable Output Up to 25V
Figure 2. RT9068 Adjustable Output Above 25V
VIN
GND
VOUT
RT9068
VIN VOUT
4.5V to 60V CIN
0.18µF
SHDN
COUT
1µF
SENSE
1.25V to 25V
R1
R2
FB
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.
Figure 3. RT9068-25/33/50 External Transistor
Application
VIN
GND
VOUT
RT9068
VIN
VOUT
4.5V to 60V CIN
0.18µF
SHDN COUT
10µF
SENSE 2.5V/3.3V/5V
100
MJD31C
VIN
GND
VOUT
RT9068
VIN
4.5V to 60V CIN
0.18µF
SHDN
COUT
1µF
SENSE R1
R2
FB
CCOMP
VOUT
1.25V to 60V
RT9068
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Figure 4. RT9068 External Transistor Application
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 :
Figure 6. Derating Curve of Maximum Power Dissipation
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. 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 TJ(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.
VIN
GND
VOUT
RT9068
VIN
4.5V to 60V CIN
0.18µF
SHDN
COUT
10µF
SENSE
100
MJD31C
1N4148 x 2 R3
VOUT
2.5V/3.3V/5V
VIN
GND
VOUT
RT9068
VIN
4.5V to 60V CIN
0.18µF
SHDN
SENSE
FB
COUT
10µF
R1
R2
CCOMP
100 VOUT
1.25V to 60V
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0 25 50 75 100 125
Ambient Temperature (°C)
Maximum Power Dissipation (W) 1
Four-Layer PCB
SOP-8 (Exposed Pad)
MSOP-8
(Exposed Pad)
RT9068
13
DS9068-06 March 2017 www.richtek.com
©
Copyright 2017 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
Figure 7. PCB Layout Guide
Layout Consideration
VOUT
SENSE
NC
NC
VIN
GND
SHDN
GND
GND
2
3
45
6
7
8
9
COUT
VOUT CIN
GND
VIN
14
DS9068-06 March 2017www.richtek.com
RT9068
©
Copyright 2017 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation.
L
D
EE1
e
A
bA1
A2
U
V
EXPOSED THERMAL PAD
(Bottom of Package)
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
Outline Dimension
15
DS9068-06 March 2017 www.richtek.com
RT9068
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. 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.
A
B
J
F
H
M
C
D
I
Y
X
EXPOSED THERMAL PAD
(Bottom of Package)
8-Lead SOP (Exposed Pad) Plastic Package
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
Option 1 Y 2.000 2.300 0.079 0.091
X 2.100 2.500 0.083 0.098
Option 2 Y 3.000 3.500 0.118 0.138

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