RT5047
Single Output LNB Supply and Control Voltage Regulator
Features
General Description
The RT5047 is a highly integrated voltage regulator
and interface IC, specifically design for supplying
power and control signals from advanced satellite
set-top box (STB) modules to the LNB down-converter
in the antenna dish or to the multi-switch box.
The device is consists of the independent current-mode
boost controller and low dropout linear regulator along
with the circuitry required for 22KHz tone shaping to
support DiSEqCTM1.x communications.
Wide Input Supply Voltage Range : 8V to 16V
Output Current Limit of 550mA with 45ms timer
Low Noise LNB Output Voltage (13.3V and 18.3V
by SEL Pin)
3% High Accuracy for 0mA to 500mA Current
Output
Push-Pull Output Stage minimizes 13.3V to
18.3V and 18.3V to 13.3V Output Transition Time
External 22kHz Tone Input
Meet DiSEqCTM 1.x Protocol
Output Short Circuit Protection
Over-temperature Protection
The RT5047 has fault protection (over-current,
over-temperature and under-voltage lockout).
The RT5047 are available in a SOP-8 (Exposed Pad)
package to achieve optimized solution for thermal
dissipation.
Ordering Information
Applications
RT5047
Package Type
SP : SOP-8 (Exposed Pad-Option 2)
LNB Power Supply and Control for Satellite Set-Top
Box
Analog and Digital Satellite Receivers/ Satellite TV,
Satellite PC cards
Pin Configurations
(TOP VIEW)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Note :
2
LX
3
VIN
4
Richtek products are :
GND
TONE
7
NC
6
SEL
5
EN
9
RoHS compliant and compatible with the current
SOP-8 (Exposed Pad)
requirements of IPC/JEDEC J-STD-020.
8
LNB
BOOST
Suitable for use in SnPb or Pb-free soldering
processes.
Simplified Application Circuit
D1
L1
VIN
CBST
CIN1
LX
BOOST
VIN
CIN2
D3
Max. 550mA
LNB
EN
RT5047
VLNB
D2
CLNB
D4
TONE
SEL
GND
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RT5047
Marking Informaton
RT5047
GSPYMDNN
RT5047GSP : Product Number
YMDNN : Date Code
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
LNB
Output Voltage for LNB.
2
BOOST
Boost Output and Tracking Supply Voltage to LNB.
3
LX
Switching Node of DC/DC Boost Converter.
4
VIN
Power Supply Input.
5
EN
LNB Output Enable.
6
SEL
LNB Output Voltage Selection Pin (Low is for 13.3V, high is for 18.3V).
7
NC
No Internal Connection. Pull to GND by 4.7k resistor.
8
TONE
9 (Exposed Pad)
GND
22kHz TONE Input.
Ground. The Exposed Pad must be soldered to a large PCB and connected
to GND for maximum power dissipation.
Function Block Diagram
LX
VIN
BOOST
OCP1
UVLO
VR1
VFB1
RF1
EN
Oscillator
Error
Amp
PWM
Controller
RF2
2-steps
Voltage
Setting
OSC
VD2
VFB2
Dynamic
Dropout
Control
Linear
Regulator
LNB
VUD
OCP2
DAC
SEL
Bandgap
Reference
VD1
TONE
22kHz Tone Shape
VFB2
OTP
VR1
Reference
Voltage
GND
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RT5047
Operation
The RT5047 integrates a current mode boost converter
and linear regulator. Use the SEL pin to control the
LNB voltage and the boost converter track is at least
greater 850mV than LNB voltage. The boost converter
is the high efficiency PWM architecture with 700kHz
operation frequency. The linear regulator has the
capability to source current up to 550mA during
continuous operation. All the loop compensation,
current sensing, and slope compensation functions are
provided internally.
OCP
Both the boost converter and the linear regulator have
independent current limit. In the boost converter
(OCP1), this is achieved through cycle-by-cycle
internal current limit (typ. 3A). In the linear regulator
(OCP2), when the linear regulator exceeds OCP more
than 48ms, the LNB output will be disabled and re-start
after 1.8s.
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Tone Circuit
This circuit is used for tone generation. Use the TONE
pin to control output amplitude of LNB.
OTP
When the junction temperature reaches the critical
temperature (typically 150C), the boost converter and
the linear regulator are immediately disabled.
UVLO
The UVLO circuit compares the VIN with the UVLO
threshold (7.7V rising typically) to ensure that the input
voltage is high enough for reliable operation. The
350mV (typ.) hysteresis prevents supply transients
from causing a shutdown.
PWM Controller
The loop compensation, current sensing, and slope
compensation functions are provided internally.
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RT5047
Absolute Maximum Ratings
(Note 1)
Supply Input Voltage, VIN ------------------------------------------------------------------------------------------- 0.3V to 30V
Output Voltage LNB, LX and BOOST Pins --------------------------------------------------------------------- 0.3V to 30V
Others Pin to GND ---------------------------------------------------------------------------------------------------- 0.3V to 6V
Power Dissipation, PD @ TA = 25C
SOP-8 (Exposed pad) ------------------------------------------------------------------------------------------------ 3.44W
Package Thermal Resistance
(Note 2)
SOP-8 (Exposed pad), JA ------------------------------------------------------------------------------------------ 29C/W
SOP-8 (Exposed pad), JC------------------------------------------------------------------------------------------ 2C/W
Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------- 260C
Junction Temperature ------------------------------------------------------------------------------------------------ 150C
Storage Temperature Range --------------------------------------------------------------------------------------- 65C to 150C
Recommended Operating Conditions
(Note 3)
Supply Input Voltage ------------------------------------------------------------------------------------------------- 8V to 16V
Ambient Temperature Range--------------------------------------------------------------------------------------- 40C to 85C
Junction Temperature Range -------------------------------------------------------------------------------------- 40C to 125C
Electrical Characteristics
(VIN (typ.) = 12V, VIN = 8V to 16V, TA = 25C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
ERR
Relative to selected VLNB target level,
ILNB = 0 to 450mA
-3
--
3
%
IIN_OFF
EN = 0, LNB output disabled
--
0.3
0.5
mA
IIN_ON
EN = 1, VLNB = 18.3V, Tone = 0V
--
10
18
mA
IIN_ON
EN = 1, VLNB = 18.3V, 22kHz TONE
Input
--
16
28
mA
Boost Switch On
Resistance
RDS(ON)
ILNB = 450mA
--
150
300
m
Switching Frequency
f SW
600
700
800
kHz
Switch Current Limit
ILIMSW
VIN = 10V, VLNB = 20.5V
--
3
--
A
Linear Regulator Voltage
Drop
VDROP
VBOOST-VLNB, ILNB = 450mA
--
0.85
--
V
Output Voltage Rise Time
TR_LNB
For VLNB = 13.3V18.3V,
CLNB = 100nF, ILNB = 450mA
--
3
10
ms
Output Voltage Pull-Down
Time
TF_LNB
For VLNB = 18.3V13.3V,
CLNB = 100nF, ILNB = 0mA
--
3
10
ms
20MHz Bandwidth Limit (GBD)
--
20
--
mVPP
General
LNB Output Accuracy,
Load and Line Regulation
Supply Current
Ripple and Noise on LNB
VRIP_PP
Output
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RT5047
Parameter
Load Regulation
Line Regulation
Symbol
Test Conditions
Min
Typ
Max
VLNB = 13.3V, ILNB = 50mA to 450mA
--
38
76
VLNB = 18.3V, ILNB = 50mA to 450mA
--
45
90
VIN = 9 to 14V, VLNB = 13.3V,
ILNB = 50mA
-10
--
10
VIN = 9 to 14V, VLNB = 18.3V,
ILNB = 50mA
-10
--
10
VOUT_LOAD
VOUT_LINE
Unit
mV
mV
Protection
Output Over-Current Limit
ILIM_LNB1
VLNB = 13.3V/18.3V
500
550
650
mA
Output Over-Current
Disable Time
TDIS_ON
VLNB Short to GND
--
45
--
ms
Output Over-Current
Disable Time
TDIS_OFF
VLNB Short to GND (GBD)
--
1800
--
ms
VIN Under-Voltage Lockout
VUVLO
Threshold
VIN Falling
--
7.35
--
V
VIN Turn On Threshold
VIN Rising
--
7.7
8
V
VIN Under-Voltage Lockout
VUVLOHYS
Hysteresis
--
350
--
mV
OTP Threshold
TOTP
--
140
--
C
OTP Hysteresis
TOTPHYS
--
15
--
C
TONE Frequency
FTONE
20
22
24
kHz
TONE Amplitude, Peak to
Peak
VTONE_PP
ILNB = 50 to 450mA, CLNB = 200nF
550
700
900
mVPP
TONE Duty Cycle
DCTONE
ILNB = 0 to 450mA, CLNB = 570nF
40
50
60
%
TONE Rise Time
TRTONE
ILNB = 0 to 450mA, CLNB = 570nF
5
10
15
s
TONE Fall Time
TFTONE
ILNB = 0 to 450mA, CLNB = 570nF
5
10
15
s
VTONE_H
1.2
--
--
V
VTONE_L
--
--
0.4
V
ITONELKG
--
5
10
A
VEN_H
1.2
--
--
V
VEN_L
--
--
0.4
V
IENLKG
--
5
10
A
VSEL_H
1.2
--
--
V
VSEL_L
--
--
0.4
V
ISELLKG
--
5
10
A
VIN_TH
TONE
TONE Logic Input
TONE Input Leakage
ENABLE, SEL Pins
EN Logic Input
EN Input Leakage
SEL Logic Input
SEL Input Leakage
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RT5047
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. JA is measured at TA = 25C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. JC is
measured at the exposed pad of the package.
Note 3. The device is not guaranteed to function outside its operating conditions.
Note 4. Operation at VIN = 16V may be limited by power loss in the linear regulator.
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RT5047
Typical Application Circuit
L1
10μH
D1
SS14
VIN
CBST
20μF
/30μF
CIN1
2x10μF
LX
BOOST
VIN
D3
SS14
CIN2
1μF
Max. 550mA
LNB
EN
RT5047
VLNB
D2
SS14
CLNB
0.1μF
D4
SMDJ20A
TONE
SEL
GND
Note :
1. D2, D3, D4, are used for surge protection. The clamping voltage of D4 is 30V, the break down voltage must be
higher than 24V as recommended.
2. The capacitor C3 should not be less than 1F for the power stability.
3. EN, TONE and SEL are connected to microcontroller directly.
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RT5047
Typical Operating Characteristics
System Efficiency vs. Output Current
Boost Efficiency vs. Output Current
95
95
90
90
Efficiency (%)
100
Efficiency (%)
100
85
80
75
85
80
75
70
70
65
65
VIN = 12V, V BOOST = 14.3V, V LNB = 13.3V
VIN = 12V, VBOOST = 14.3V
60
0.00
0.10
0.20
0.30
0.40
0.50
60
0.00
0.60
0.10
Tone Amplitude vs. Temperature
0.40
0.50
0.60
Tone Amplitude vs. Output Current
0.90
0.90
0.85
0.85
Tone Amplitude (V)
Tone Amplitude (V)
0.30
Output Current (A)
Output Current (A)
0.80
0.75
0.70
0.65
0.80
0.75
0.70
0.65
0.60
0.60
VIN = 12V, VLNB = 13.3V, TONE enable
VIN = 12V, VLNB = 13.3V, TONE enable
0.55
0.55
-50
-25
0
25
50
75
100
0
125
0.1
0.2
0.3
0.4
0.5
0.6
Output Current (A)
Temperature (°C)
Output Voltage v.s Temperature
Output Voltage vs. Output Current
19
19
18
18
VLNB_ 18.3V
VLNB_18.3
Output Voltage (V)
Output Voltage (V)
0.20
17
16
15
14
VLNB_13.3
13
17
16
15
14
VLNB_13.3V
13
VIN = 12V
VIN = 12V
12
12
-50
-25
0
25
50
75
100
Temperature (°C)
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125
0.00
0.10
0.20
0.30
0.40
0.50
0.60
Output Current (A)
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RT5047
Under Voltage Lockout vs. Temperature
Over Current Protect vs. Temperature
0.70
Under Voltage Lockout (V)1
8.00
Current (A)
0.65
0.60
0.55
7.80
7.60
7.40
7.20
VIN = 12V, VLNB = 13.3V
0.50
7.00
-25
0
25
50
75
100
125
-50
-25
0
25
50
75
100
Temperature (°C)
Temperature (°C)
Tone Output
Output Voltage Transition Rising
125
VLNB
(5V/Div)
VIN = 12V VSEL from 0V to 3.3V,
CLNB = 0.1F, VLNB from 13V to 18V
VLNB_ac
(200mV/Div)
VIN = 12V
VSEL
(2V/Div)
Time (50s/Div)
Time (500s/Div)
Output Voltage Transition Falling
Power On Sequence
VLNB
(5V/Div)
VIN = 12V, VSEL from 3.3V to 0V,
CLNB = 1F, VLNB from 18V to 13V
VSEL
(2V/Div)
VIN
(10V/Div)
VBOOST
(10V/Div)
VLNB
(10V/Div)
Time (500s/Div)
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VIN = 12V
Time (5ms/Div)
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RT5047
Over Current Protection
VBOOST
(5V/Div)
VLNB
(5V/Div)
ILNB
(500mA/Div)
VIN = 12V
Time (500ms/Div)
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RT5047
Application Information
Boost Converter/Linear Regulator
with half of the inductor ripple current as shown in the
The 5047 integrates a current-mode boost converter
and linear regulator. Use the SEL pin to control the
LNB voltage and the boost converter track is at least
greater 800mV than the LNB voltage. The boost
converter is high efficiency PWM architecture with
700kHz operation frequency. The linear regulator has
the capability to source current up to 550mA during
continuous operation. All the loop compensation,
current sensing, and slope compensation functions are
provided internally.
following equation :
The RT5047 has current limiting on the boost converter
and the LNB output to protect the IC against short
circuits. The internal MOSFET will turn off when the LX
current is higher than 3A cycle-by-cycle. The LNB
output will turn off when the output current higher than
the 550mA and 45ms and turn-on after 1800ms
automatically.
Input Capacitor Selection
The input capacitor reduces voltage spikes from the
input supply and minimizes noise injection to the
converter. A 30F capacitance is sufficient for most
applications. Nevertheless, a higher or lower value may
be used depending on the noise level from the input
supply and the input current to the converter. Note that
the voltage rating of the input capacitor must be greater
than the maximum input voltage.
Inductor Selection
The inductance depends on the maximum input current.
As a general rule, the inductor ripple current range is
20% to 40% of the maximum input current. If 40% is
selected as an example, the inductor ripple current can
be calculated according to the following equations :
VOUT IOUT(MAX)
VIN
= 0.4 IIN(MAX)
IIN(MAX) =
IRIPPLE
where η is the efficiency of the converter, IIN(MAX) is
the maximum input current, and IRIPPLE is the
inductor ripple current. The input peak current can
IPEAK = 1.2 x IIN(MAX)
note that the saturated current of the inductor must be
greater than IPEAK. The inductance can eventually be
determined according to the following equation :
η VIN VOUT VIN
2
L
0.4 VOUT I OUT(MAX)fOSC
2
where f OSC is the switching frequency. For better
system performance, a shielded inductor is preferred to
avoid EMI problems.
Boost Output Capacitor Selection
The RT5047 boost regulator is internally compensated
and relies on the inductor and output capacitor value
for overall loop stability. The output capacitor is in the
30F to 50F range with a low ESR, as strongly
recommended. The voltage rating on this capacitor
should be in the 25V to 35V range since it is connected
to the boost VOUT rail.
The output ripple voltage is an important index for
estimating chip performance. This portion consists of
two parts. One is the product of the inductor current
with the ESR of the output capacitor, while the other
part is formed by the charging and discharging process
of the output capacitor. As shown in Figure 1, VOUT1
can be evaluated based on the ideal energy
equalization. According to the definition of Q, the Q
value can be calculated as the following equation :
Q = 1 IIN 1 IL IOUT IIN 1 IL IOUT
2
2
2
V
IN 1 = COUT VOUT1
VOUT fOSC
where f OSC is the switching frequency and IL is the
inductor ripple current. Bring COUT to the left side to
estimate the value of VOUT1 according to the following
equation :
VOUT1 =
D IOUT
COUT fOSC
then be obtained by adding the maximum input current
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RT5047
where D is the duty cycle and η is the boost converter
efficiency. Finally, take ESR into consideration, the
overall output ripple voltage can be determined by the
operation. The 350mV (typ.) hysteresis prevents supply
transients from causing a shutdown. Once the input
voltage exceeds the UVLO rising threshold, start-up
following equation :
begins. When the input voltage falls below the UVLO
falling threshold, all IC internal functions will be turned
off by the controller.
VOUT = IIN ESR
D IOUT
COUT fOSC
The output capacitor, COUT, should be selected
accordingly.
ΔIL
Input Current
Inductor Current
Output Current
Time
(1-D)TS
Output Ripple
Voltage (ac)
Time
ΔVOUT1
Over-Current Protection
The RT5047 features an over-current protection
function to prevent chip damage from high peak
currents. Both the boost converter and the linear
regulator have independent current limit. In the boost
converter, this is achieved through cycle-by-cycle
internal current limit. During the ON-period, the chip
senses the inductor current that is flowing into the LX
pin. The internal NMOS will be turned off if the peak
inductor current reaches the current-limit value of 3A
(typ.).When the linear regulator exceeds 550mA (typ.)
more than 45ms, the LNB output will be disabled.
During this period of time, if the current limit condition
disappears, the OCP will be cleared and the part
restarts. If the part is still in current limit after this time
period, the linear regulator and boost converter will
automatically disable to prevent the part from
overheating.
Figure 1. The Output Ripple Voltage without the
Short Circuit Protection
Contribution of ESR
Schottky Diode Selection
Schottky
diodes
are
chosen
for
their
low
forward-voltage drop and fast switching speed.
However, when making a selection, important
parameters such as power dissipation, reverse voltage
rating, and pulsating peak current should all be taken
into consideration. A suitable Schottky diode’s reverse
voltage rating must be greater than the maximum
output voltage and its average current rating must
exceed the average output current. The chosen diode
should also have a sufficiently low leakage current level,
since it increases with temperature.
Under-Voltage Lockout (UVLO)
The UVLO circuit compares the input voltage at VIN
with the UVLO threshold (7.7V rising typically) to
ensure that the input voltage is high enough for reliable
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If the LNB output is shorted to ground, and more than
45ms, the RT5047 will be disabled 1.8s then enable
automatically.
Over-Temperature Protection
When the junction temperature reaches the critical
temperature (typically 140 oC), the boost converter and
the linear regulator are immediately disabled. When the
junction temperature cools down to a lower
temperature threshold specified, the RT5047 will be
allowed to restart by normal start operation.
LNB Output Voltage
The RT5047 has voltage control function on the LNB
output. This function provides 4 levels for the common
standards and compensation if the cable line has
voltage drop. These voltage levels are defined in table
1. The rise time and fall time of the VLNB is 3mS (typ.).
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RT5047
Table 1
SEL Pin Status
LNB Output Voltage
0
13.3V
1
18.3V
Tone Generation
The RT5047 provides the tone generation function, please refer to the Figure 2. Set the TONE pin with 22kHz logic
signal, the LNB linear regulator output will carry a 22kHz, 700mV peak to peak signal for DiSEqC 1.x communication.
It can meet base-band timings of 500s (±100s) for a one-third bit PWK coded signal period on a nominal 22kHz
(±20 %).
LNB
13.3V or
18.3V
700m
V
VLNB output
TONE when
TONE signal
rise up
VLNB close
TONE after
TONE signal
detect time
TONE signal
detect time
3.3V
TONE
signal
0V
Figure 2. Tone Generation Options
Pull-Down Rate Control
The output linear stage provides approximately 40mA
of pull-down capability. This ensures that the output
If loading is 1000mA
25ms
volts are ramped from 18.3V to 13.3V in a reasonable
amount of time.
Over-Current Disable Time
OCP1=1000mA
OCP1=1000mA
25ms
OCP2=550mA
20ms
20ms
1800ms
If LNB is shorted to GND
OCP1=250mA
OCP1=250mA
If the LNB output current exceeds 550mA, typical, for
more than 45ms, then the LNB output will be disabled
and device enters a TON = 45ms/TOFF = 1800ms
OCP2=550mA
25ms
25ms
OCP2=138mA
OCP2=138mA
20ms
20ms
1800ms
routine. It will be returned to normal operation after a
successful soft-start process.
Inrush Current
At start-up or during a LNB reconfiguration event, a
transient surge current above the normal DC operating
level can be provided by the IC. This current increase
can be as high as 550mA, typical, for as long as
required, up to a maximum of 45ms.
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RT5047
The RT5047 can handle up to 500mA during
continuous operation.
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 :
PD(MAX) = (TJ(MAX) TA) / JA
where TJ(MAX) is the maximum junction temperature,
TA is the ambient temperature, and JA is the junction to
ambient
thermal
resistance.For
recommended
operating condition specifications, the maximum
junction temperature is 125C. The junction to ambient
thermal resistance, JA, is layout dependent. For
Maximum Power Dissipation (W) 1
DC Current
5.0
Four-Layer PCB
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0
25
50
75
100
125
Ambient Temperature (°C)
Figure 3. Derating Curve of Maximum Power
Dissipation
SOP-8 (Exposed Pad) package, the thermal resistance,
JA, is 29C/W on a standard JEDEC 51-7 four-layer
thermal test board. The maximum power dissipation at
TA = 25C can be calculated by the following formula :
PD(MAX) = (125C 25C) / (29C/W) = 3.44W for
SOP-8 (Exposed Pad) package
The maximum power dissipation depends on the
operating ambient temperature for fixed TJ(MAX) and
thermal resistance, JA. The derating curve in Figure 3
allows the designer to see the effect of rising ambient
temperature on the maximum power dissipation.
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is a registered trademark of Richtek Technology Corporation.
DS5047-00
March 2015
RT5047
Layout Consideration
For high frequency switching power supplies, the PCB layout is important to get good regulation, high efficiency and
stability. The following descriptions are the guidelines for better PCB layout.
For good regulation, place the power components as close as possible. The traces should be wide and short
enough especially for the high-current loop.
Minimize the size of the LX node and keep it wide and shorter.
The exposed pad of the chip should be connected to a strong ground plane for maximum thermal consideration.
The CIN, CBST and CLNB
should be placed as closed
as possible to R T 5 0 4 7 f o r
good filter.
D 3 and D 4 should be placed
as closed as possible to
VOUT for surge protection.
VOUT
D4
CLNB1
The exposed pad of the chip
should be connected to
analog ground plane for
thermal consideration.
D2
LNB
TONE
D3
BOOST
CBST1
CBST2
CBST3
NC
GND
D1
LX
SEL
L1
VIN
VIN
CIN1
The TONE, SEL and EN pin
should be connected to MCU
or GND. Do not floating these
pins.
EN
CIN2
The inductor should be placed as close as possible to the L X pin to minimize the
noise coupling into other circuits.
LX node copper area should be minimized for reducing EMI
Place the power components as close as possible. The traces should be wide and
short especially for the high-current loop.
Figure 4. PCB Layout Guide
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
DS5047-00
March 2015
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
15
RT5047
Outline Dimension
Dimensions In Millimeters
Symbol
Dimensions In Inches
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.
Copyright © 2015 Richtek Technology Corporation. All rights reserved.
www.richtek.com
16
is a registered trademark of Richtek Technology Corporation.
DS5047-00
March 2015
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