RT8468A

®
RT8468A
500V Power MOSFET Integrated High Efficiency Constant
Current LED Driver
General Description
Features
The RT8468A integrates a 500V power MOSFET and a
PWM controller. It is used for step-down converters by
well controlling the internal MOSFET and regulating a
constant output current. The output duty cycle of the
RT8468A can be up to 100% for wider input voltage
applications, such as E27 and PAR30 off-line LED lighting
products.
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The RT8468A also features a 47kHz fixed frequency
oscillator, an internal 220mV precision reference, and a
PWM comparator with latching logic. The accurate output
LED current is achieved by an averaging current feedback
loop and the LED current dimming can be easily controlled
via the ACTL pin. The RT8468A also has multiple features
to protect the controller from fault conditions, including
Under Voltage Lockout (UVLO), Over Current Protection
(OCP) and Over Voltage Protection (OVP). Additionally,
to ensure the system reliability, the RT8468A is built with
the thermal protection function.
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Built-In 500V/1A Power MOSFET
Low Cost and Efficient Buck Converter Solution
Universal Input Voltage Range with Off-Line
Topology
Adjustable Constant LED Current
Dimmable LED Current by ACTL
Output LED String Open Protection
Output LED String Short Protection
Output LED String Over Current Protection
Built-in Thermal Protection
SOP-7 Package
RoHS Compliant and Halogen Free
Applications
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E27, PAR30, Offline LED Lights
Marking Information
RT8468AGS : Product Number
RT8468A
GSYMDNN
The RT8468A is housed in a SOP-7 package. Thus, the
components in the whole LED driver system can be made
very compact.
YMDNN : Date Code
Simplified Application Circuit
500V
CIN
R1
RD
RT8468A
VCC
C1
VC
DRAIN
R3
ACTL
SENSE
RVC
SGND
CVC
SOURCE
RS
DF
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DS8468A-00 February 2013
D1
L1
LED+
COUT
LED-
is a registered trademark of Richtek Technology Corporation.
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1
RT8468A
Ordering Information
Pin Configurations
RT8468A
(TOP VIEW)
Package Type
S : SOP-7
SOURCE
Lead Plating System
G : Green (Halogen Free and Pb Free)
Note :
7
DRAIN
SGND
2
VCC
3
6
ACTL
SENSE
4
5
VC
Richtek products are :
`
SOP-7
RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020.
`
Suitable for use in SnPb or Pb-free soldering processes.
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
SOURCE
Internal Power MOSFET Source Connection.
2
SGND
Ground.
3
VCC
Power Supply Input. For good bypass, a ceramic capacitor near the VCC pin is
required.
4
SENSE
LED Current Sense Input. Typical sensing threshold is 220mV.
5
VC
PWM Loop Compensation Node.
6
ACTL
Analog Dimming Control. The typical effective dimming range is between 0.1V to 1.2V.
7
DRAIN
Internal Power MOSFET Drain Connection.
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is a registered trademark of Richtek Technology Corporation.
DS8468A-00 February 2013
RT8468A
Function Block Diagram
+
+
-
Chip Enable
12V
17V/8V
OSC
OVP
+
VCC
35V
DRAIN
S
R
SOURCE
R
+
-
Control
Circuit
VC
Dimming
ACTL
-
SENSE
+
SGND
Operation
The RT8468A is a high voltage Buck PWM current mode
driver with an integrated 500V power MOSFET. The start
up voltage of RT8468A is around 17V. Once VCC is above
17V, RT8468A will maintain operation until VCC drops
below 8V.
than 100% duty. It is not always that the GATE turns low
in each OSC cycle. The GATE turns low until the current
comparator (CCOMP) resets the gate driver. The GATE
will be set high again by OSC and the next switching
cycle repeats.
The RT8468A's main control loop consists of a 47kHz
fixed frequency oscillator, an internal 220mV precision
current sense threshold OPAMP (OP1), and a PWM
comparator (CCOMP) with latching logic. In normal
operation, the GATE turns high when the gate driver is
set by the oscillator (OSC). The lower the average of the
sensed current is below the loop-regulated 220mV
threshold, the higher the VC pin voltage (OP1 output) will
go high. Higher the VC voltage means longer the GATE
turn-on period. The GATE of RT8468A can turn on more
The ACTL voltage of RT8468A is internally biased to 0.6V.
The adjustment of the regulated sense current threshold
(dimming) can be achieved by varying ACTL pin voltage.
The typical range of ACTL voltage adjustment is between
0.1V and 1.2V.
Copyright © 2013 Richtek Technology Corporation. All rights reserved.
DS8468A-00 February 2013
The RT8468A is equipped with protection from several fault
conditions, including input voltage Under Voltage Lockout
(UVLO), Over Current Protection (OCP) and VIN/VOUT
Over Voltage Protection (OVP). Additionally, to ensure
the system reliability, the RT8468A is built with internal
thermal protection function.
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3
RT8468A
Absolute Maximum Ratings
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(Note 1)
Supply Input Voltage, VCC to SGND --------------------------------------------------------------------------------ACTL Voltage to SGND (Note 2) ------------------------------------------------------------------------------------VC Voltage to SGND ----------------------------------------------------------------------------------------------------SENSE Voltage to SGND ----------------------------------------------------------------------------------------------DRAIN to SOURCE Voltage, VDS -------------------------------------------------------------------------------------DRAIN Current, ID @ TC = 25°C ---------------------------------------------------------------------------------------DRAIN Current, ID @ TC = 100°C -------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C
SOP-7 -----------------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 3)
SOP-7, θJA -----------------------------------------------------------------------------------------------------------------Junction Temperature ----------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------------ESD Susceptibility, Except DRAIN & SOURCE Pin (Note 4)
HBM (Human Body Model) ---------------------------------------------------------------------------------------------MM (Machine Model) -----------------------------------------------------------------------------------------------------
Recommended Operating Conditions
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−0.3V to 40V
−0.3V to 8V
−0.3V to 6V
−1V to 0.3V
−0.3V to 550V
1.4A
0.9A
0.5W
200.2°C/W
150°C
260°C
−65°C to 150°C
2kV
200V
(Note 5)
Supply Input Voltage, VCC ---------------------------------------------------------------------------------------------- 16V to 31V
Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C
Electrical Characteristics
(VCC = 24VDC, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
Supply Voltage
Input Start-Up Voltage
VST
--
16
19
V
Under Voltage Lockout
Threshold Hysteresis
ΔVUVLO
--
8
9
V
Maximum Startup Current
IST(MAX)
--
250
300
μA
Input Supply Current
ICC
After Start-Up, VCC = 24V
--
2
5
mA
Input Quiescent Current
IQC
Before Start-Up, VCC = 15V
--
--
2
μA
Current Sense Voltage
VSENSE
(Note 6)
209
220
231
mV
Sense Input Current
ISENSE
VSENSE = 0.2V
--
20
--
μA
VC Sourcing Current
IVC_Sr
VSENSE = −150mV
--
18.5
--
μA
VC Sinking Current
IVC_Sk
VSENSE = −230mV
--
165
--
μA
VC Threshold for PWM
Switch Off
VVC
1.15
1.25
1.35
V
Current Sense Amplifier
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is a registered trademark of Richtek Technology Corporation.
DS8468A-00 February 2013
RT8468A
Parameter
Symbol
Test Conditions
Min
Typ
Max
Unit
38
47
56
kHz
--
--
100
%
Oscillator
Switching Frequency
fSW
Maximum Duty in Transient
Operation
DMAX(TR)
Maximum Duty in Steady State
Operation
DMAX
--
97
--
%
Blanking Time
tBLANK
--
300
--
ns
--
650
--
ns
--
1
20
μA
LED Current On Threshold at ACTL VACTL_ON
--
1.2
--
V
LED Current Off Threshold at ACTL VACTL_OFF
--
0.1
0.2
V
Minimum Off Time
VC = 3V
(Note 7)
LED Dimming
Analog Dimming ACTL Pin Input
Current
IACTL
VACTL = 1.2V
Internal MOSFET
Static Drain-Source On-Resistance RDS(ON)
VVC = 3V, ID = 0.6A
--
5
--
Ω
Drain-Source Leakage Current
IDSS
VVC = 0V, VDS = 500V
--
--
10
μA
Output Capacitance
COSS
VCC = 0V, VDS = 25V, f = 1MHz
--
14
40
pF
VOVP
VCC pin
32
35
38
V
--
150
--
°C
OVP
Over Voltage Protection
Thermal Protection
Thermal Shutdown Temperature
TSD
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. If a 1MΩ resistor is connected between the control input and ACTL pin, the control input voltage can be up to 36V.
Note 3. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7.
Note 4. Devices are ESD sensitive. Handling precaution is recommended.
Note 5. The device is not guaranteed to function outside its operating conditions.
Note 6. The RT8468A achieves precise LED average current with a current feedback loop to sense the average LED current, in
the deep discontinuous mode operation especially when a small inductor is used small current offset might occur
due to current waveform distortion of the nature of the discontinuous operation. This offset current is consistent over
production.
Note 7. Guaranteed by design, not subjected to production test.
Copyright © 2013 Richtek Technology Corporation. All rights reserved.
DS8468A-00 February 2013
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
5
RT8468A
Typical Application Circuit
AC In
~
CIN
10µF
R1
1M
R2
1M
RD
10
C1
4.7µF
RVC
3.3k
CVC
3.3nF
RT8468A
3 VCC
DRAIN 7
5 VC
R3
1M
ACTL 6
ZD1
SENSE 4
2
SGND
SOURCE 1
Optional
RS
2
DF
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D1
L1
1m
COUT
LED+
ZD2
48V
Optional
100mA
LED-
is a registered trademark of Richtek Technology Corporation.
DS8468A-00 February 2013
RT8468A
Typical Operating Characteristics
55
Switching Frequency (kHz)1
Switching Frequency (kHz)1
Switching Frequency vs. Temperature
Switching Frequency vs. VCC
55
51
47
43
39
51
47
43
39
35
35
0
4
8
12
16
20
24
28
32
36
-50
-25
0
VCC (V)
25
50
75
100
125
100
125
Temperature (°C)
RDS(ON) vs. VCC
RDS(ON) vs. Temperature
8.0
30
7.5
25
6.5
RDS(ON) (Ω)
RDS(ON) (Ω)
7.0
6.0
5.5
20
15
10
5.0
5
4.5
0
4.0
0
4
8
12
16
20
24
28
32
-50
36
-25
0
VCC (V)
7LED
6LED
5LED
4LED
3LED
90%
90
17LED
15LED
12LED
10LED
9LED
8LED
110VAC
180VAC
220VAC
264VAC
95%
95
85%
85
80%
80
75%
75
90%
90
85%
85
80%
80
70%
70
75%
75
VIN_AC = 110V to 264V, IOUT = 100mA
65%
65
110 130 150 170 190 210 230
70%
70
VIN_AC = 110V to 264V, IOUT = 100mA
250
VIN (V)
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75
100%
100
Efficiency (%)
Efficiency (%)
95%
95
50
Efficiency vs. Number of LEDs
Efficiency vs. VIN
100%
100
25
Temperature (°C)
270
3
5
7
9
11
13
15
17
Number of LEDs (pcs)
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RT8468A
LED Current vs. VACTL
LED Current vs. Output Voltage
115
100
110
LED Current (mA)
LED Current (mA)
120
80
60
40
105
100
95
20
VIN_AC = 110V, IOUT = 100mA,
LED 17 pcs, L = 1mH, VACTL = 0 to 2.5V
VIN_AC = 110V, IOUT = 100mA, LED 17 pcs, L = 1mH
0
90
0
0.25 0.5 0.75
1
1.25 1.5 1.75
2
2.25 2.5
8
15
22
29
36
43
50
Output Voltage (V)
VACTL (V)
LED Current vs. Temperature
LED Current vs. Input Voltage
105
110
108
106
LED Current (mA)
LED Current (mA)
103
101
99
97
104
102
100
98
96
94
VIN_AC = 85V to 265V,
IOUT = 100mA, LED 17 pcs, L = 1mH
95
92
IOUT = 100mA
90
85
115
145
175
205
235
265
-50
-25
0
25
50
75
100
125
Input Voltage (V)
Temperature (°C)
Sense Voltage vs. Input Voltage
VDS Voltage and Inductor Current
230
150
Sense Voltage(mV)
225
220
IOUT = 200mA (L = 0.68mH)
215
IOUT = 100mA (L = 1mH)
210
VDrain_Source
(100V/Div)
205
200
195
IL
(200mA/Div)
IOUT = 60mA (L = 1.5mH)
190
185
VIN_AC = 85V to 265V, LED 17 pcs
180
90
115
140
165
190
215
240
265
VIN_AC = 110V, IOUT = 100mA, 17 LEDs, L = 1mH
Time (5μs/Div)
Input Voltage (V)
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is a registered trademark of Richtek Technology Corporation.
DS8468A-00 February 2013
RT8468A
Power On
Power Off
VIN
(200V/Div)
VIN
(200V/Div)
VOUT
(50V/Div)
VOUT
(50V/Div)
IOUT
(50mA/Div)
IOUT
(50mA/Div)
VIN_AC = 110V, IOUT = 100mA, 17 LEDs, L = 1mH
Time (100ms/Div)
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DS8468A-00 February 2013
VIN_AC = 110V, IOUT = 100mA, 17 LEDs, L = 1mH
Time (100ms/Div)
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RT8468A
Application Information
The RT8468A is a high efficiency PWM Buck LED driver
for high brightness LED application. Its high side floating
gate driver is used to control the Buck converter with
internal MOSFET and regulate the constant output current.
The RT8468A can achieve high accuracy LED output current
via the average current feedback loop control. The internal
sense voltage (220mV typ.) is used to set the average
output current. The oscillator frequency is fixed at 47kHz
to get better switching performance. Once the average
current is set by the external resistor, RS, the output LED
current can be dimmed by varying the ACTL voltage.
Under Voltage Lockout (UVLO)
The RT8468A includes a UVLO feature with 9V hysteresis.
The GATE terminal turns on when VIN rises over 17V (typ.).
The GATE terminal turns off when VIN falls below 8V (typ.).
Setting Average Output Current
The output current that flows through the LED string is
set by an external resistor, RS, which is connected between
the GND and SENSE terminal. The relationship between
output current, IOUT, and RS is shown below :
0.22
IOUT =
(A)
RS
Analog Dimming Control
The ACTL terminal is driven by an external voltage, VACTL,
to adjust the output current to an average value set by RS.
The voltage range for VACTL to adjust the output current is
from 0.2V to 1.3V. If VACTL becomes larger than 1.3V, the
output current value will just be determined by the external
resistor, RS.
IOUTavg = (0.22V/RS ) ×
VACTL − 0.2
1.1
Component Selection
For component selection, an example is shown below for
a typical RT8468A application, where VIN = 110 to 90VAC/
60Hz, LED output voltage = 30V, and output current =
200mA. The user can follow this procedure to design
applications with wider AC voltage input and DC output
voltage as well.
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Start-up Resistor
Start-up resistor should be chosen not to exceed the
maximum start-up current. Otherwise, the RT8468A may
latch low and will never start. Start-up current = 130V/R1
for 110VAC regions, 260V/R1 for 220VAC regions. The
typical start-up current is 250μA.
Input Diode Bridge Rectifier Selection
The current rating of the input bridge rectifier is dependent
on the VOUT /VIN transformation ratio. The voltage rating of
the input bridge rectifier, VBR, on the other hand, is only
dependent on the input voltage. Thus, the VBR rating is
calculated as below :
VBR = 1.2 × ( 2 × VAC(MAX) )
where VAC(MAX) is the maximum input voltage (RMS) and
the parameter 1.2 is used for safety margin.
For this example :
VBR = 1.2 × ( 2 × VAC(MAX) ) = (1.2 × 2 × 110) = 187V
If the input source is universal, VBR will reach 466V. In
this case, a 500V, 0.5A bridge rectifier can be chosen.
Input Capacitor Selection
The input capacitor supplies the peak current to the
inductor and flattens the current ripple on the input. The
low ESR condition is required to avoid increasing power
loss. The ceramic capacitor is recommended due to its
excellent high frequency characteristic and low ESR. For
maximum stability over the entire operating temperature
range, capacitors with better dielectric are suggested. The
minimum capacitor is given by :
VOUT(MAX) × IOUT(MAX)
CIN ≥
⎡( 2 × VAC(MIN) )2 − V 2DC(MIN) ⎤ ×η × fAC
⎣
⎦
where fAC is the AC input source frequency and η is the
efficiency of whole system.
Notice that VDC(MIN) is the minimum voltage at bridge
rectifier, output and VDC(MIN) should be larger than 2 x
VOUT(MAX).
For a 90 to 264VAC universal input range, the VDC(MIN) is
90V, therefore the LED string voltage VOUT(MAX) should be
less than 45V.
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DS8468A-00 February 2013
RT8468A
For this particular example :
30 × 0.2
CIN ≥
= 13.7μF
2
⎡( 2 × 90) − 902 ⎤ × 0.9 × 60
⎣
⎦
In addition, the voltage rating of the input filter capacitor,
VCIN, should be large enough to handle the input
voltage.
VCIN ≥ (1.2 × 2 × VAC(MAX) ) = (1.2 × 2 × 110) = 187V
Thus, a 22μF / 250V electrolytic capacitor can be chosen
in this case. Due to its large ESR, the electrolytic capacitor
is not suggested for high current ripple applications.
Inductor Selection
The inductor value and operating frequency determine the
ripple current according to a specific input and output
voltage. The ripple current, ΔIL, increases with higher VIN
and decreases with higher inductance, as shown in
equation below :
⎤
⎡V
⎤ ⎡ V
ΔIL = ⎢ OUT ⎥ × ⎢1− OUT ⎥
f
x
L
V
⎣
⎦ ⎣
IN ⎦
To optimize the ripple current, the RT8468A operates the
Buck converter in BCM (Boundary-Condition Mode). The
largest ripple current will occur at the highest VIN. To
guarantee that the ripple current stays below the specified
value, the inductor value should be chosen according to
the following equation :
L=
=
VOUT × TS × (1− D)
2 × IOUT
30 × 20.83μs × (1− 0.333)
= 1.04mH
2 × 0.2
where D is the duty cycle and TS is the switching period.
Forward Diode Selection
When the power switch turns off, the path for the current
is through the diode connected between the switch output
and ground. This forward biased diode must have minimum
voltage drop and recovery time. The reverse voltage rating
of the diode should be greater than the maximum input
voltage and the current rating should be greater than the
maximum load current.
In reality, the peak current through the diode is more than
the maximum output current. This component current
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DS8468A-00 February 2013
rating should be greater than 1.2 times the maximum load
current and the diode reverse voltage rating should be
greater than 1.2 times the maximum input voltage,
assuming a ± 20% output current ripple.
The peak voltage stress of diode is :
VD = 1.2 × ( 2 × VAC(MAX) ) = 1.2 × ( 2 × 110) = 187V
The current rating of diode is :
ID = 1.2 × IOUT,PK = 1.2 × 1.2 × 0.2 = 0.288A
If the input source is universal (VIN = 90V to 264V), VD will
reach 466V. A 500V, 2A ultra-fast diode can be used in
this example.
Output Capacitor Selection
The selection of COUT is determined by the required ESR
to minimize output voltage ripple. Moreover, the amount
of bulk capacitance is also a key for COUT selection to
ensure that the control loop is stable. Loop stability can
be checked by viewing the load transient response. The
output voltage ripple, ΔVOUT, is determined by :
ΔVOUT =
VO × (1− D)
8 × L × COUT × fOSC2
where fOSC is the switching frequency. Multiple capacitors
placed in parallel may be needed to meet the ESR and
RMS current handling requirement. Dry tantalum, special
polymer, aluminum electrolytic and ceramic capacitors are
all common selections and available in surface mount
packages. Tantalum capacitors have the highest
capacitance density, but it is important to only use ones
that pass the surge test for use in switching power
supplies. Special polymer capacitors offer very low ESR
value, but with the trade-off of lower capacitance density.
Aluminum electrolytic capacitors have significantly higher
ESR, but still can be used in cost-sensitive applications
for ripple current rating and long term reliability
considerations.
Thermal Protection
A thermal protection feature is included to protect the
RT8468A from excessive heat damage. When the junction
temperature exceeds a threshold of 150°C, the thermal
protection will turn off the GATE terminal.
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Soldering Process of Pb-free Package Plating
To meet the current RoHS requirements, pure tin is
selected to provide forward and backward compatibility
with both the current industry standard SnPb-based
soldering processes and higher temperature Pb-free
processes. In the whole Pb-free soldering processes pure
tin is required with a maximum 260°C (<10s) for proper
soldering on board, referring to J-STD-020 for more
information.
Thermal Considerations
Maximum Power Dissipation (W)1
RT8468A
0.6
Four-Layer PCB
0.5
0.4
0.3
0.2
0.1
0.0
0
25
50
75
100
125
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
Layout Considerations
maximum power dissipation can be calculated by the
following formula :
For best performance of the RT8468A, the following layout
guidelines should be strictly followed.
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.
The hold up capacitor, C1, must be placed as close as
possible to the VCC pin.
`
The output capacitor, COUT, must be placed as close as
possible to the LED terminal.
For recommended operating condition specifications, the
maximum junction temperature is 125°C. The junction to
ambient thermal resistance, θJA, is layout dependent. For
SOP-7 package, the thermal resistance, θJA, is 200.2°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 formula :
`
The power ground (PGND) should be connected to a
strong ground plane.
`
Place the sense resistor RS as close to the SOURCE
pin as possible.
`
Keep the main current traces as short and wide as
possible.
PD(MAX) = (125°C − 25°C) / (200.2°C/W) = 0.5W for
SOP-7 package
`
Place L1, RS, and DF as close to each other as possible.
Ambient Temperature (°C)
Figure 1. Derating Curve of Maximum Power Dissipation
The maximum power dissipation depends on the operating
ambient temperature for fixed T J(MAX) and thermal
resistance, θJA. The derating curve in Figure 1 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.
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RT8468A
Place the Input Capacitor
CIN to the DRAIN pin as
close as possible
CIN
VC
ACTL
6
7
RVCC2
VCC
CVC
COUT
CS
LED-
PGND
3
VCC
4
2
SENSE
RS
L1
SGND
SENSE
SOURCE
RB
D2
LED+
RVCC1
RVC
5
DRAIN
VIN
RACTL
C1
DF
Place the capacitor C1
as close as possible to
the VCC.
Place the Output capacitor
COUT as close as possible
to LED terminal
Figure 2. PCB Layout Guide
Copyright © 2013 Richtek Technology Corporation. All rights reserved.
DS8468A-00 February 2013
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
13
RT8468A
Outline Dimension
Symbol
Dimensions In Millimeters
Dimensions In Inches
Min.
Max.
Min.
Max.
A
4.801
5.004
0.189
0.197
B
3.810
3.988
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
F1
2.464
2.616
0.097
0.103
H
0.100
0.254
0.004
0.010
I
0.050
0.254
0.002
0.010
J
5.791
6.200
0.228
0.244
M
0.400
1.270
0.016
0.050
7-Lead SOP Plastic Package
Richtek Technology Corporation
5F, No. 20, Taiyuen 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.
www.richtek.com
14
DS8468A-00 February 2013