DIODES AL8806

AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Pin Assignments
The AL8806 is a step-down DC/DC converter designed to
drive LEDs with a constant current. The device can drive up
to 8 LEDs, depending on the forward voltage of the LEDs, in
series from a voltage source of 6V to 30V. The AL8806
switches at frequency up to 1MHz. This allows the use of
small size external components, hence minimizing the PCB
area needed.
Maximum output current of AL8806 is set via an external
resistor connected between the VIN and SET input pins.
Dimming is achieved by applying either a DC voltage or a
PWM signal at the CTRL input pin. An input voltage of 0.4V
or lower at CTRL switches off the output MOSFET simplifying
PWM dimming.
MSOP-8EP
SET
GND
GND
CTRL
Features
•
•
•
•
•
•
•
•
•
LED driving current up to 1.5A
Better than 5% accuracy
High efficiency up to 98%
Operating input voltage from 6V to 30V
High switching frequency up to 1MHz
PWM/DC input for dimming control
Built-in output open-circuit protection
MSOP8-EP: Available in “Green” Molding Compound (No
Br, Sb) with lead Free Finish/RoHS Compliant (Note 1)
Notes:
1
2
3
4
AL8806
VIN
N/C
SW
SW
8
7
6
5
Applications
•
•
High power MR16 lamps
General illumination lamps
Multi-die LED driver
1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at:
http://www.diodes.com/products/lead_free.html
Typical Application Circuit
DFLS230LH
D1
RSET
0R089
450µF
D4
AL8806
Document number: DS35144 Rev. 2 - 2
C1
SET
C2
AL8806
SW
12VAC
DFLS230LH
x4
GND
~
D3
VIN
D2
CTRL
NEW PRODUCT
Description
Multidie
LED
1µF
33µH L1
D5
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
NEW PRODUCT
Pin Descriptions
Pin
Name
Pin
Number
MSOP-8EP
Descriptions
SW
GND
5, 6
2, 3
Switch Pin. Connect inductor/freewheeling diode here, minimizing track length at this pin to reduce EMI.
GND Pin
CTRL
4
SET
1
VIN
8
EP
N/C
EP
7
Dimming and On/Off Control Input.
• Leave floating for normal operation.
(VCTRL = VREF = 2.5V giving nominal average output current IOUTnom = 0.1/RS)
• Drive to voltage below 0.4V to turn off output current
• Drive with DC voltage (0.5V < VCTRL < 2.5V) to adjust output current from 20% to 100% of IOUTnom
• A PWM signal (low level ≤ 0.4V and high level > 2.6; transition times less than 1us) allows the output
current to be adjusted below the level set by the resistor connected to SET input pin.
Set Nominal Output Current Pin. Configure the output current of the device.
Input Supply Pin. Must be locally decoupled to GND with > 2.2µF X7R ceramic capacitor – see
applications section for more information.
Exposed pad/TAB connect to GND and thermal mass for enhanced thermal impedance
no connection
Absolute Maximum Ratings (TA = 25°C)
Symbol
ESD HBM
ESD MM
VIN
VSW
VCTRL
ISW-RMS
ISW-PK
TJ
TLEAD
TST
Caution:
Parameter
Human Body Model ESD Protection
Machine Model ESD Protection
Continuous VIN pin voltage relative to GND
SW voltage relative to GND
CTRL pin input voltage
DC or RMS switch current
Peak switch current (<10%)
Junction Temperature
Lead Temperature Soldering
Storage Temperature Range
Ratings
Unit
2.5
200
-0.3~36
-0.3~36
-0.3 ~ 6
1.65
3
150
300
-65 to +150
kV
V
V
V
V
A
A
°C
°C
°C
The absolute maximum ratings are rated values exceeding which the product could suffer physical damage. These values must therefore not be
exceeded under any condition.
Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when
handling and transporting these devices
Recommended Operating Conditions (TA = 25°C)
Symbol
VIN
VCTRLH
VCTRLDC
VCTRLL
ISW
fOSC
TJ
Parameter
Operating Input Voltage relative to GND
Voltage High for PWM dimming relative to GND
Voltage range for 20% to 100% DC dimming relative to GND
Voltage Low for PWM dimming relative to GND
DC or RMS switch current
Switching Frequency
Junction Temperature Range
AL8806
Document number: DS35144 Rev. 2 - 2
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Min
Max
Unit
6.0
2.6
0.5
0
30
5.5
2.5
0.4
1.5
1
125
V
V
V
V
A
MHz
°C
-40
June 2011
© Diodes Incorporated
AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Electrical Characteristics
VIN =12V, TA=25oC, unless otherwise specified.
Symbol
Parameter
VINSU
NEW PRODUCT
VINSH
IQ
IS
VTH
VTH-H
ISET
RCTRL
VREF
RDS(on)
ISW_Leakage
θJA
Notes:
Conditions
Min
Typ.
Internal regulator start up threshold VIN rising
Internal regulator hysteresis
threshold
Quiescent current
Input supply Current
Set current Threshold Voltage
Set threshold hysteresis
SET pin input current
CTRL pin input resistance
Internal Reference Voltage
On Resistance of SW MOSFET
Switch leakage current
Thermal Resistance Junction-toAmbient (Note 4)
VIN falling
Output not switching (Note 2)
CTRL pin floating f = 250kHz
VCTRL ≥ 2.6V or floating.
VSET = VIN-0.1
Referred to internal reference
ISW = 1A
VIN =30V
MSOP-8EP (Note 3)
100
95
1.8
100
±20
16
50
2.5
0.18
69
Max
Unit
5.9
V
300
mV
350
5
105
µA
mA
mV
mV
µA
kΩ
V
Ω
μA
22
0.35
0.5
°C/W
2. AL8806 does not have a low power standby mode but current consumption is reduced when output switch is inhibited: VSENSE = 0V. Parameter is
tested with VCTRL ≤ 2.5V
3. Measured on an FR4 51x51mm PCB with 2oz copper standing in still air. Refer to figure 5 for the device derating curve.
4. Test condition: Device mounted on FR-4 PCB (51mm x 51mm 2oz copper, minimum recommended pad layout on top layer and thermal vias to
bottom layer ground plane. For better thermal performance, larger copper pad for heat-sink is needed
AL8806
Document number: DS35144 Rev. 2 - 2
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
.
Typical Performance Characteristics (TA = 25°C unless otherwise stated)
900
400
L = 33µH
V CTRL = 0V
V SET = V IN
TA = 25 °C
350
Frequency (kHz)
250
IIN (µA)
TA = 25°C
700
300
200
150
NEW PRODUCT
V IN = 12V
1 LED
RSET = 150m Ω
800
100
600
L = 68µH
500
400
300
200
L = 100µH
50
0
100
0
1.6
1.4
5
0
10
15
20
25
30
VI N (V)
Supply Current (not switching) vs. Input Current
60
3
4
VCTR L (V)
Switching Frequency vs. VCT RL
5
TA = 25 °C
40
RSET = 100mΩ
ICT RL (µA)
LED CURRENT (A)
1.2
0.8
2
V SET = V IN = 12V
L =68µH
1
1
80
RSET = 68mΩ
TA = 25°C
0
RSET = 150mΩ
20
0
0.6
-20
0.4
-40
0.2
0
-60
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
V CTRL (V)
ICTRL vs VCTRL
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
CTRL VOLTAGE (V)
LED Current vs. VCTRL
3
2.52
V CTRL = Open
V SET = V IN = 12V
2.5
2.51
V CTRL (V)
V CTRL (V)
2
1.5
1
2.50
V CTRL = Open
V SET = V IN
2.49
TA = 25 °C
0.5
0
0
5
10
15
20
VIN (V)
V CTRL vs. Input Voltage
(CTRL pin open circuit)
AL8806
Document number: DS35144 Rev. 2 - 2
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2.48
-40
-15
10
35
60
85
Ambient Temperature (°C)
V CTRL vs. Temperature
110
June 2011
© Diodes Incorporated
AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Typical Performance Characteristics Continued (TA = 25°C unless otherwise stated)
200
0.9
180
0.8
160
3.5
0.7
140
3.0
0.6
1 LED
R SET = 150m Ω
LED Current Error (%)
L = 68µH
0.5
2.5
LED Current Error
0.4
2.0
ILED
1.5
120
100
80
60
0.3
40
1.0
0.2
0.5
0.1
VCTRL = Open
VSET = VIN 12V
20
0.0
0%
0
0
100%
20%
40%
60%
80%
PWM Duty Cycle
ILED vs. PWM Duty Cycle
260
TA = 25°C
0
5
15
20
25
VIN (V)
RDS(ON) vs. Input Voltage
30
18
16
125
V SENSE
120
220
14
12
115
V SW
200
V SENSE (mV)
RDS(ON) (mΩ)
10
130
240
180
160
110
10
105
8
100
6
4
95
140
RSET = 150m Ω
L = 68µH
V IN = 12V
1 LED Load
90
120
VCTRL = Open
VSET = VIN 12V
100
-40
-15
10
35
60
85
AMBIENT TEMPERATURE (°C)
SW RDS(ON) vs. Temperature
100%
85
110
80
0
2
2
0
4
6
Time (µs)
SW Output Switching Characteristics
-2
8
L = 33µH
RSET = 150m Ω
90%
TA = 25 °C
2 LED
80%
70%
Duty Cycle
NEW PRODUCT
4.0
V SW
4.5
LED Current (A)
V IN = 12V
RDS(ON) (mΩ)
1
5.0
60%
50%
40%
30%
20%
10%
0%
6
9
12
15
18
21
24
Input Voltage (V)
Duty Cycle vs. Input Voltage
AL8806
Document number: DS35144 Rev. 2 - 2
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Typical Operating Performance Characteristics (TA = 25°C unless otherwise stated)
1.5A nominal LED current
1.0A nominal LED current
10%
10%
8%
2 LEDs
6%
6%
2 LEDs
5 LEDs
4%
DEVIATION
% ERROR
6 LEDs 7 LEDs
7 LEDs 8 LEDs
3 LEDs
4%
2%
0%
1 LED
-2%
8 LEDs
5 LEDs
3 LEDs
4 LEDs
2%
1 LED
0%
-2%
-4%
-4%
-6%
-6%
TA = 25°C
L = 33µH
RS = 66.67mΩ
-8%
-10%
6
9
12 15 18 21 24
INPUT VOLTAGE (V)
27
30
-8%
TA = 25°C
L = 33µH
RS = 100mΩ
-10%
6
9
12 15 18 21 24
INPUT VOLTAGE (V)
27
30
700
700
TA = 25°C
L = 33µH
RS = 66.67mΩ
600
SWITCHING FREQUENCY (kHz)
SWITCHING FREQUENCY (kHZ)
500
400
300
200
1 LED
100
T A = 25°C
L = 33µH
RS = 100mΩ
600
500
400
300
200
1 LED
100
2 LEDs 3 LEDs
4 LEDs 5 LEDs 6 LEDs
2 LEDs 3 LEDs 4 LEDs 5 LEDs 6 LEDs 7 LEDs 8 LEDs
0
6
9
12
15 18 21 24
INPUT VOLTAGE (V)
27
0
6
30
100%
9
8 LEDs
7 LEDs
12 15 18 21 24
INPUT VOLTAGE (V)
100%
4 LEDs
5 LEDs
6 LEDs
7 LEDs 8 LEDs
4 LEDs
7 LEDs
5 LEDs 6 LEDs
27
30
8 LEDs
3 LEDs
95%
95%
2 LEDs
3 LEDs
90%
EFFICIENCY
NEW PRODUCT
8%
6 LEDs
4 LEDs
2 LEDs
85%
90%
1 LED
85%
1 LED
80%
80%
TA = 25°C
L = 33µH
RS = 100mΩ
TA = 25°C
L = 33µH
RS = 66.67mΩ
75%
6
9
12 15 18 21 24
INPUT VOLTAGE (V)
AL8806
Document number: DS35144 Rev. 2 - 2
75%
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30
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6
9
12 15 18 21 24
INPUT VOLTAGE (V)
27
30
June 2011
© Diodes Incorporated
AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Application Information
AL8806 Operation
In normal operation, when voltage is applied at VIN, the AL8806 internal switch is turned on. Current starts to flow through
sense resistor RSET, inductor L1, and the LEDs. The current ramps up linearly, and the ramp rate is determined by the input
voltage VIN and the inductor L1.
DFLS230LH
D1
RSET
12V
4.7µF 100nF
SET
C3
AL8806
Multidie
LED
1µF
SW
C2
GND
C1
CTRL
VIN
NEW PRODUCT
0R082
33µH
GND
L1
Figure 1: Typical Application Circuit
This rising current produces a voltage ramp across RSET. The internal circuit of the AL8806 senses the voltage across RSET
and applies a proportional voltage to the input of the internal comparator.
When this voltage reaches an internally set upper threshold, the internal switch is turned off. The inductor current continues
to flow through RSET, L1, the LEDs and the schottky diode D1, and back to the supply rail, but it decays, with the rate of decay
determined by the forward voltage drop of the LEDs and the schottky diode.
This decaying current produces a falling voltage at R1, which is sensed by the AL8806. A voltage proportional to the sense
voltage across RSET is applied at the input of the internal comparator. When this voltage falls to the internally set lower
threshold, the internal switch is turned on again. This switch-on-and-off cycle continues to provide the average LED current
set by the sense resistor RSET.
LED Current Control
The LED current is controlled by the resistor RSET in Figure 1.
Connected between VIN and SET the nominal average output current in the LED(s) is defined as:
ILED =
VTHD
RSET
If the CTRL pin is driven by an external voltage (higher than 0.4V and lower than 2.5V), the average LED current is:
ILED =
VCTRL VTHD
VREF R SET
For example for a desired LED current of 1.33A and a default voltage VCTRL=2.5V the resulting resistor is:
R SET =
VTHD VCTRL
0 .1 2 . 5
=
≈ 75mΩ
ILED VREF
1.33 2.5
DC Dimming
The CTRL pin can be driven by an external DC voltage (VCTRL), to adjust the output current to a value below the nominal
average value defined by RSET. The LED current decreases linearly with the CTRL voltage when 0.5V ≤ VCTRL ≤ 2.5V, as
shown on page 4 for 4 different current levels.
Note that 100% brightness setting corresponds to VCTRL = VREF, nominally 2.5V. For any voltage applied on the CTRL pin that
is higher than VREF, the device will not overdrive the LED current and will still set the current according to the equation
VCTRL = VREF.
When the CTRL voltage falls below the threshold, 0.4V, the output switch is turned off which allows PWM dimming.
AL8806
Document number: DS35144 Rev. 2 - 2
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Applications Information (continued)
PWM Dimming
LED current can be adjusted digitally, by applying a low frequency Pulse Width Modulated (PWM) logic signal to the CTRL
pin to turn the device on and off. This will produce an average output current proportional to the duty cycle of the control
signal. In particular, a PWM signal with a max resolution of 10bit can be applied to the CTRL pin to change the output current
to a value below the nominal average value set by resistor RSET. To achieve this resolution the PWM frequency has to be
lower than 500Hz, however higher dimming frequencies can be used - at the expense of dimming dynamic range and
accuracy.
700
LED current [mA]
600
500
400
300
200
100
0
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
7%
8%
9%
10%
PWM dimming [%]
Figure 2. PWM Dimming at 500Hz
70
60
LED current [mA]
NEW PRODUCT
Typically, for a PWM frequency of 500Hz the accuracy is better than 1% for PWM ranging from 1% to 100%.
50
40
30
20
10
0
0%
1%
2%
3%
4%
5%
6%
PWM dimming [%]
Figure 3. Low duty cycle PWM Dimming at 500Hz
The PWM pin is designed to be driven by both 3.3V and 5V logic levels directly from a logic output with either an open drain
output or push-pull output stage.
AL8806
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HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Applications Information (continued)
Soft Start
NEW PRODUCT
The AL8806 does not have in-built soft-start action – this provides very fast turn off of the output the stage improving PWM
dimming accuracy; nonetheless, adding an external capacitor from the CTRL pin to ground will provide a soft-start delay. This
is achieved by increasing the time taken for the CTRL voltage to rise to the turn-on threshold and by slowing down the rate of
rise of the control voltage at the input of the comparator. Adding a capacitor increases the time taken for the output to reach
90% of its final value, this delay is 0.1ms/nF, but will impact on the PWM dimming accuracy depending on the delay
introduced.
Figure 4. Soft start with 22nF capacitor on CTRL pin (VIN = 30V, ILED = 667mA, 1 LED)
AL8806
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Applications Information (continued)
Reducing output ripple
Peak to peak ripple current in the LED(s) can be reduced, if required, by shunting a capacitor C2 across the LED(s) as shown
already in the circuit schematic.
A value of 1μF will reduce the supply ripple current by a factor three (approx.). Proportionally lower ripple can be achieved
with higher capacitor values. Note that the capacitor will not affect operating frequency or efficiency, but it will increase
start-up delay, by reducing the rate of rise of LED voltage. By adding this capacitor the current waveform through the LED(s)
changes from a triangular ramp to a more sinusoidal version without altering the mean current value.
The small size of ceramic capacitors makes them ideal for AL8806 applications. X5R and X7R types are recommended
because they retain their capacitance over wider voltage and temperature ranges than other types such as Z5U.
A 2.2μF input capacitor is sufficient for most intended applications of AL8806; however a 4.7μF input capacitor is suggested
for input voltages approaching 30V.
Diode Selection
For maximum efficiency and performance, the rectifier (D1) should be a fast low capacitance Schottky diode with low reverse
leakage at the maximum operating voltage and temperature. The Schottky diode also provides better efficiency than silicon
PN diodes, due to a combination of lower forward voltage and reduced recovery time.
It is important to select parts with a peak current rating above the peak coil current and a continuous current rating higher
than the maximum output load current. In particular, it is recommended to have a diode voltage rating at least 15% higher
than the operating voltage to ensure safe operation during the switching and a current rating at least 10% higher than the
average diode current. The power rating is verified by calculating the power loss through the diode.
Schottky diodes, e.g. B240 or B140, with their low forward voltage drop and fast reverse recovery, are the ideal choice for
AL8806 applications.
Thermal and layout considerations
For continuous conduction mode of operation, the absolute maximum junction temperature must not be exceeded. The
maximum power dissipation depends on several factors: the thermal resistance of the IC package θJA, PCB layout, airflow
surrounding the IC, and difference between junction and ambient temperature.
The maximum power dissipation can be calculated using the following formula:
PD(MAX ) =
(125°C − 25°C) = 1.45 W
where
69°C / W
TJ(MAX) is the maximum operating junction temperature,
TA is the ambient temperature, and
θJA is the junction to ambient thermal resistance.
The recommended maximum operating junction temperature, TJ, is 125°C and so maximum ambient temperature is
determined by the AL8806’s junction to ambient thermal resistance, θJA. To support high LED drive at higher ambient
temperatures the AL8806 has been packaged in thermally enhanced MSOP-8EP package.
θJA, is layout dependent and the AL8806 in MSOP-8EP’s θJA
on a 51 x 51mm single layer PCB with 2oz copper standing
in still air is approximately 69°C/W.
Therefore the maximum power dissipation at TA = 25°C is:
(125°C − 25°C) = 1.45 W
PD(MAX ) =
69°C / W
Figure 5, shows the power derating of the AL8806 on an
FR4 51x51mm PCB with 2oz copper standing in still air.
As the ambient temperature increases and/or the PCB area
reduces the maximum power dissipated by the AL8806 will
decrease.
1600
Power dissipation (mW)
NEW PRODUCT
Capacitor Selection
1400
MSOP-8EP
1200
1000
800
600
400
200
0
-40 -25 -10
5 20 35 50 65 80
Ambient temperature (°C)
95 110 125
Figure 5. Derating Curve
AL8806
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Applications Information (continued)
PCB Layout
When laying out the PCB for the AL8806 the following should be observed:
1. The decoupling capacitor C1 has to be placed as close as possible to VIN
2. The sense resistor, RSET, has to be placed as close as possible to VIN and SET
3. The anode of the freewheel diode (D1), the SW pin and the inductor have to be placed as close as possible to each
other to avoid ringing.
SET
AL8806
D1
C2
SW
GND
C1
VIN
To avoid
radiated EMI
keep dashed
tracks as
short as
possible
CTRL
NEW PRODUCT
RSET
L1
Figure 6. PCB Layout
The AL8806 has two evaluation boards available on request (AL8806EV4 and AL8806EV6). Information can be found on the
Diodes website and from a Diodes’ sales representative.
Application Example
A typical application example for the AL8806 is the MR16 lamp; which normally operate from 12VDC or 12VAC supplies, using
conventional electromagnetic transformers or electronic transformers.
As a replacement for MR16 halogen lamps, LED lamps offer a more energy efficient solution - radiating no heat and no Ultra
Violet light. The low thermal impedance of the AL8806 and its 1.5A switch capability allows it drive some of the latest multidie LEDs; which increases the lamp’s luminance.
This application example is intended to fit into the base connector space of an MR16 style LED lamp. The design has been
optimized for part count and thermal performance for a multi-die LED in the Lens section as well as EMI conformance.
Figure 7. MR16 Schematic
AL8806
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Applications Information (continued)
The output of the 12V transformer is fed into the bridge rectifier, comprising of D2, D3, D4 and D5. C10 offers an optional EMI
filtering at the input. (see figure 9)
Capacitor, CBULK, (capacitors C1 and C2 on the PCB and BOM are multiple components to reduce size) forms the bulk
reservoir capacitance - used to sustain operation of the device during the low part of the rectified AC wave. In the case of a
system driving two LEDs at 1.1A, one 470µF plus 47µF capacitors are required.
NEW PRODUCT
Capacitors C3 and C9 provide local decoupling for the AL8806 and for the schottky freewheeling diode, D1. It is important that
C3 is as close as possible to the AL8806’s VIN pin and that C9 is as close to the VIN and shottky diode as possible, as reflected
in the layout shown below in figure 8.
The LED current is determined by the total resistance between the VIN and SET pins (R1 and R2 in figures 7 (schematic) and 8
(top PCB) and BOM).
C4 decouples the LED connections, again to minimize EMI, as well as smoothing the current.
D1 operates as the freewheeling diode, providing a current path for the LED current when the power switch at SW pin is off.
Capacitors C5 to C9, 1.5nF have been added to improve the overall EMI performance. C5 is connected across the Supply
pins to reduce radiation via the wiring. C6 and C7 also assist the reduction of EMI via the wiring. C8 snubs high frequency
radiation from the harmonics in the switching regulator.
A large number of vias have been used to improve the grounding effect throughout the PCB to improve the evaluation board’s
EMI performance.
Figure 8. AL8806EV6 evaluation board (Top)
AL8806
Document number: DS35144 Rev. 2 - 2
Figure 9. AL8806EV6 evaluation board (Bottom)
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Applications Information (continued)
AL8806EV6 BOM
Count Designator Description
Manufacturer
Part Number
Radial,
10 x 12.5mm
Rubycon
25ZLH470M
1
C1
Capacitor, 470uF, 25V Aluminium Electrolytic
1
C2
Capacitor, 4.7µF 10% 50V X7R
1210
Kemet
C1210X475K5RAC
C3, C9, C10 Capacitor, 100nF 10% 50V X7R
0805
Kemet
NIC
NMC0805X7R104K50TRPF
Capacitor, 100nF 10% 50V X7R
1206
Kemet
NIC
NMC1206X7R104K50TRPF
Capacitor, 1.5nF 10% 50V or 100V, COG
0805
generic
6.6 x 6.6mm
Coilcraft
NIC
Würth
MSS7341-153ML
NPIS64D150MTRF
744777115
MPZ2012S300A
3
NEW PRODUCT
Package
1
C4
4
C5 ~ C8
1
C1210X475K5RAC
C1206104K5RAC7800
L1
Inductor, shielded, 15µH 20%
1
L2
Inductor, ferrite bead, 6A, 30ohms @100MHz
0805
TDK
1
R1
Resistor, 0.15ohms 1% 250ppm 125mW
0805
generic
1
R2
Resistor, 0.2ohms 1% 250ppm 125mW
0805
generic
1
D1
Diode, schottky, 30V 2A DFLS230
(alternatives: DFLS230L or LH)
PowerDi123
Diodes Inc
DFLS230-7
4
D2 ~ D5
Diode, Super Barrier Rectifier, 30V 2A
SBR2U30
PowerDi123
Diodes Inc
SBR2U30P1-7
1
U1
IC, LED Driver, AL8806
MSOP-8EP
Diodes Inc
AL8806MP8-13
The AL8806 guarantees high level of performance both with 12VAC and 12VDC power supply.
AL8806
Document number: DS35144 Rev. 2 - 2
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© Diodes Incorporated
AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
Ordering Information
NEW PRODUCT
AL8806 XXX - XX
Package
Packing
MP8 : MSOP-8EP
13 : 13” Tape & Reel
Tape and Reel
Part Number Suffix
Device
Package Code
Packaging
(Note 5)
Quantity
AL8806MP8-13
MP8
MSOP-8EP
2500/Tape & Reel
Notes:
-13
5. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at
http://www.diodes.com/datasheets/ap02001.pdf.
Marking Information
MSOP-8EP
(Top View)
a~z : Lead Free
A~Z : Green
MSOP-8EP
Y : Year : 0~9
W : Week: A~Z : 1~26 week;
a~z : 27~52 week;
z represents 52 and 53 week
Logo
Part Number
AL8806
Part Number
AL8806MP8-13
Package
MSOP-8EP
Package Information
MSOP-8EP
AL8806
Document number: DS35144 Rev. 2 - 2
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AL8806
HIGH EFFICIENCY 30V 1.5A BUCK LED DRIVER
IMPORTANT NOTICE
DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS
DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION).
NEW PRODUCT
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other
changes without further notice to this document and any product described herein. Diodes Incorporated does not assume any liability
arising out of the application or use of this document or any product described herein; neither does Diodes Incorporated convey any
license under its patent or trademark rights, nor the rights of others. Any Customer or user of this document or products described
herein in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all the companies
whose products are represented on Diodes Incorporated website, harmless against all damages.
Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized
sales channel.
Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall
indemnify and hold Diodes Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees
arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized application.
Products described herein may be covered by one or more United States, international or foreign patents pending. Product names
and markings noted herein may also be covered by one or more United States, international or foreign trademarks.
LIFE SUPPORT
Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without
the express written approval of the Chief Executive Officer of Diodes Incorporated. As used herein:
A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body, or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided
in the labeling can be reasonably expected to result in significant injury to the user.
B.
A critical component is any component in a life support device or system whose failure to perform can be reasonably expected
to cause the failure of the life support device or to affect its safety or effectiveness.
Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or
systems, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements
concerning their products and any use of Diodes Incorporated products in such safety-critical, life support devices or systems,
notwithstanding any devices- or systems-related information or support that may be provided by Diodes Incorporated. Further,
Customers must fully indemnify Diodes Incorporated and its representatives against any damages arising out of the use of Diodes
Incorporated products in such safety-critical, life support devices or systems.
Copyright © 2011, Diodes Incorporated
www.diodes.com
AL8806
Document number: DS35144 Rev. 2 - 2
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© Diodes Incorporated