AP8802

AP8802
1A LED STEP-DOWN CONVERTER
Description
Pin Assignments
The AP8802 is a step-down DC/DC converter designed to drive
(Top View)
LEDs with a constant current. The device can drive up to thirteen
LEDs, depending on the forward voltage of the LEDs, in series from
a voltage source of 8V to 48V. Series connection of the LEDs
provides identical LED currents resulting in uniform brightness and
eliminating the need for ballast resistors. The AP8802 switches at
frequencies up to 700kHz.
(Top View)
8 CTRL
SET
GND 2
7 GND
AP8802
NC 3
6 SW
VIN 4
5 SW
This allows the use of small size
SO-8
external components, hence minimizing the PCB area needed.
5 SW
(Top View)
SET
GND
NC
NC
VIN
Dimming is
achieved by applying either a DC voltage or a PWM signal at the
CTRL input pin. An input voltage of 0.2V or lower at CTRL shuts
down the output at SW and puts the device into a low-current
standby state.
1
2
3
4
5
10 CTRL
AP8802
9
8
7
6
GND
NC
SW
SW
U-DFN3030-10
Features
•
LED driving current up to 1A
•
High efficiency up to 92%
•
Operating input voltage up to 48V
•
Commercial & industrial lighting
•
High switching frequency up to 700kHz
•
Small LCD panel backlight
•
PWM/DC input for dimming control
•
Appliances interior lighting
•
Built-in output open-circuit protection
•
Architecture Detail lighting
•
AP8802
8 CTRL
7 GND
6 SW
SO-8EP
Maximum output current of AP8802 is set via an external resistor
connected between the VIN and SET input pins.
SET
GND 2
NC 3
VIN 4
Applications
SO-8, SO-8EP and U-DFN3030-10 are available in “Green”
Molding Compound (No Br, Sb)
•
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
•
Halogen and Antimony Free. “Green” Device (Note 3)
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl)
and <1000ppm antimony compounds.
Typical Application Circuit
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Pin Descriptions
Name
SO-8
SO-8EP
U-DFN3030-10
SW
6, 5
6, 5
7, 6
GND
2
2
2, 9
SET
1
1
1
Function
Switch Pin. Connect inductor/freewheeling diode here, minimizing track length at this pin
to reduce EMI.
GND pin
Set Nominal Output Current Pin. Configure the output current of the device.
Dual function dimming control pin.
CTRL
8
8
10
•
Input voltage of 0.2V or lower forces the device into low current standby mode
and shuts off the output.
•
A PWM signal (driven by an open-drain/collector source) allows the output
current to be adjusted over a wide range up to 100%.
•
An analog voltage between 0.3V and 2.5V adjusts the output current between
25% and 200% of the current set by 0.2V/RS.
The input impedance is about 50kΩ, and if the pin is left open VCTRL = VREF
VIN
4
4
5
NC
3
3
3, 4, 8
Input Supply Pin. Must be locally bypassed.
No connection
Exposed pad: Internally connected to IC substrate.
It should be connected to GND and as large as possible thermal mass for improved
EP
-
EP
EP
thermal impedance and power dissipation capability.
However the exposed pad is not a Power GND return path. The dedicated GND pins must
be connected to 0V. See Land Pad diagrams.
Functional Block Diagram
Figure. 1 Functional Block Diagram
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Absolute Maximum Ratings (TA = +25°C) (Note 4)
Symbol
Rating
Unit
VIN
VIN pin voltage
Parameter
-0.3 to +50
V
VSW
SW voltage
-0.3 to +50
V
VCTRL
CTRL Pin Input Voltage
-0.3 to +6
V
VSENSE
SET Voltage (Note 5)
+0.3 to -5
V
TJ
Junction Temperature
150
o
Lead Temperature Soldering
300
o
-65 to +150
o
TLEAD
TST
Note:
Storage Temperature Range
C
C
C
4 All voltages unless otherwise stated are measured with respect to GND.
5. VSENSE is measured with respect to VIN.
Caution: Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are
stress ratings only; functional operation of the device at these or any other conditions exceeding those indicated in this
specification is not implied. Device reliability may be affected by exposure to absolute maximum rating conditions for extended
periods of time.
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
VCTRLDC
VCTRL
fOSC
TA
Duty Cycle
Notes:
Parameter
Min
Max
Unit
Operating input voltage relative to GND
8.0
48.0
V
Voltage range for 24% to 200% DC dimming relative to GND (Note 6)
0.3
2.5
V
Voltage low for PWM dimming relative to GND
0
0.2
V
Maximum switching frequency (Note 7)
—
625
kHz
Ambient temperature range
-40
+105
°C
Using inductor ≥ 100µH (Note 8)
0.10
0.95
—
6. For 100% brightness either leave floating or connect to 1.25V relative to GND.
7. AP8802 will operate at higher frequencies but accuracy will be affected due to propagation delays and also increased power dissipation will occur
due to increased switching losses.
8. For most applications the LED current will be within 8% over the duty cycle range specified. Duty cycle accuracy is also dependent on propagation
delay. Smaller size inductors can be used but LED current accuracy may be greater than 8% at extremes of duty cycle. This is most noticeable at
low duty cycles (less than 0.1) or when the input voltage is high and only one LED is being driven.
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Electrical Characteristics (TA = +25°C, VIN = 12V; unless otherwise specified.)
Symbol
IOUT
IQ
Parameter
Continuous switch current
Conditions
(Note 9)
Quiescent Current
VTHD
Internal Threshold Voltage
VSENSEHYS
Sense threshold hysteresis
SET
SET pin input current
VREF
Internal Reference Voltage
RDS(ON)
On Resistance of MOSFET
VSET = VIN -0.2
ISW = 0.8A
ISW_LEAKAGE Switch leakage current
SO-8 (Note 10)
Thermal Resistance Junction-to-
θJA
Ambient
θJC
Notes:
Thermal Resistance Junction-to-Case
Min
Typ.
Max
Unit
—
—
1
A
—
75
120
μA
184
200
216
mV
—
15
—
%
—
5
—
μA
—
1.25
—
V
—
0.65
1.10
Ω
—
—
8
μA
—
82
—
°C/W
SO-8EP (Note 10)
—
45
—
°C/W
U-DFN3030-10 (Note 10)
—
38
—
°C/W
SO-8 (Note 10)
—
52
—
°C/W
SO-8EP (Note 10)
—
7
—
°C/W
U-DFN3030-10 (Note 10)
—
24
—
°C/W
9. Refer to figure 8 for the device derating curve.
10. Test condition for SO-8, SO-8EP and U-DFN3030-10: Device mounted on FR-4 PCB, 2”x2”, 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.
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Typical Characteristics
1.256
0.9
0.8
1.254
0.7
CTRL VOLTAGE (V)
NON-SWITCHING SUPPLY CU RRENT (mA)
0.6
0.5
0.4
0.3
1.252
1.250
1.248
0.2
1.246
0.1
0
0
1.244
-40 -25 -10 5 20 35 50 65 80 95 110 125
AMBIENT TEMPERATURE (°C)
Figure. 3 VCTRL vs. Ambient Temperature
4
8 12 16 20 24 28 32 36 40 44 48
INPUT VOLTAGE (V)
Figure. 2 Supply Current (not switching) vs. Input Voltage
1.2
1000
900
800
LED CURRENT (mA)
RDS(ON) (Ω)
1.0
0.8
0.6
0.4
700
600
500
400
300
200
0.2
100
0
-40 -25 -10 5 20 35 50 65 80 95 110 125
AMBIENT TEMPERATURE (°C)
Figure. 4 RDS(ON) vs. Ambient Temperature
0
0
1.0
1.5
2.0
RSET RESISTANCE (Ω)
Figure. 5 LED Current vs. RSET
2.5
800
1200
RSET = 0.3Ω
SWITCHING FREQUENCY (kHz)
RSET = 0.2Ω
1000
LED CURRENT (mA)
0.5
800
600
RSET = 0.68Ω
400
200
700
600
500
400
300
200
100
0
0
0
0.5
1
1.5
2
CTRL VOLTAGE (V)
Figure. 6 LED Current vs. VCTRL
AP8802
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0
0.5
1
1.5
2
2.5
CTRL VOLTAGE (V)
Figure. 7 Switching Frequency vs. VCTRL
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AP8802
1A LED STEP-DOWN CONVERTER
Typical Characteristics
(TA = +25°C, VIN = 40V, L = 68µH; unless otherwise stated.)
OUTPUT CURRENT DEVIATION (%)
10
8
6
4
2
0
-2
-4
-6
-8
-10
6
12
18
24
30
36
42
48
6
INPUT VOLTAGE (V)
Figure. 8 LED Current vs. Input Voltage
18
24
30
36
42
48
INPUT VOLTAGE (V)
Figure 9. Efficiency vs. Input Voltage
100
TA = +25°C
450
90
RSET = 0.2Ω
L = 68µH
400
80
350
DUTY CYCLE (%)
SWITCHING FREQUENCY (kHz)
500
12
300
250
200
1 LED
150
100
70
60
50
40
30
20
50
3 LEDs
5 LEDs
10
7 LEDs
0
6
12
18
24
30
36
42
48
INPUT VOLTAGE (V)
Figure. 10 Switching Frequency vs. Input Voltage
Document number: DS31766 Rev. 9 - 2
6
12
18
24
30
36
42
48
SUPPLY VOLTAGE (V)
Figure. 11 Duty Cycle vs. Input Voltage
Fig.13 Start-Up Showing LED Current Soft Start
Fig. 12 Steady State Waveforms
AP8802
0
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AP8802
1A LED STEP-DOWN CONVERTER
Application Information
LED Current Control
The LED current is controlled by the resistor RSET in Figure 14 connected between VIN and SET. The nominal average output current in the
LED(s) with the CTRL pin open circuit is defined as:
ILED =
VTHD
R SET
where VTHD is the voltage between the VIN and SET pins and is nominally 200mV.
Figure. 14 Typical Application Circuit for ILED = 1A
Inductor Selection
This section highlights how to select the inductor suitable for the application requirements in terms of switching frequency, LED current
accuracy and temperature.
500
68
Switching Frequency @ ILED = 700mA
450
12V - 3 LEDs
24V - 5 LEDs
400
FREQUENCY (kHz)
100
47
350
48V - 10 LEDs
300
68
150
250
220
100
200
150
150
47
100
220
470
68
100
50
150
470
220
470
0
0
50
100
150
200
250
300
350
400
450
500
INDUCTOR VALUE (µH)
Figure. 15 Switching Frequency vs. Inductor Value
The inductor influences the LED current accuracy that the system is able to provide. The following section highlights how to select the
inductor in relation to the device packages and the LED current, while maintaining the chip temperature below 70°C.
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Application Information (cont.)
AP8802 U-DFN3030-10 Minimum Recommended Inductor - LED Current 1A
8% Accuracy, <70°C Case Temperature
12
11
10
NUMBER of LEDs
9
8
7
6
5
4
3
2
1
0.0
5.0
20.0
25.0
30.0
35.0
40.0
Supply Voltage (V)
Figure. 16 U-DFN3030-10 Recommended Inductor with 1A LED Current
10.0
15.0
45.0
AP8802 SO-8EP Minimum Recommended Inductor
8% Accuracy, <70°C Case Temperature, 1A Target Current
12
11
10
NUMBER of LEDs
9
8
7
6
5
4
3
2
1
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
SUPPLY VOLTAGE (V)
Figure. 17 SO-8EP Recommended Inductor with 1A LED Current
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Application Information (cont.)
AP8802 SO-8 Minimum Recommended Inductor
8% Accuracy, <70°C Case Temperature
12
11
10
NUMBER of LEDs
9
8
7
6
5
4
3
2
1
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
Supply Voltage (V)
Figure. 18 SO-8 Recommended Inductor with 700mA LED Current
Capacitor Selection
The small size of ceramic capacitors makes them ideal for AP8802 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 AP8802.
A 4.7μF input capacitor is suggested for application with an input voltage equal or higher than 40V.
Diode Selection
Schottky diodes, e.g. B2100 or B1100, with their low forward voltage drop and fast reverse recovery, are the ideal choice for AP8802
applications.
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Application Information (cont.)
LED Current Adjustment/Dimming
The LED current for the AP8802 can be adjusted by driving the CTRL with a digital signal (PWM dimming) or by driving the CTRL with a DC
voltage between 0.3V and 2.5V (dc dimming).
If the CTRL pin is driven by an external voltage (lower than 2.5V), the average LED current is:
ILED =
VCTRL VTHD
×
VREF R SET
where VREF is nominally 1.25V
1200
LED Current @
VCTRL = 1.25V
0.39
1000
0.2
LED Current @
VCTRL = 2.5V
LED CURRENT (mA)
0.47
800
LED Current @
VCTRL = 0.625V
0.56
0.68
0.33
600
0.39
0.2
0.82
0.47
1
0.56
0.68
0.33
0.82
0.47
1
0.68
0.82
1
400
200
0
0
1.2
1.5
2
1.2
1.2
3
1.5
2
1.5
3
2
3
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
3.0
RSET VALUE (Ω)
Figure. 19 LED Current Setting vs. RSET and VCTRL
Figure 19 shows that reducing the CTRL voltage by a factor of 2 also reduces the LED current by a factor of 2. The AP8802 has the ability
vary the LED current by a factor of 2 above the default value set by RSET down to a factor of 0.24 of the nominal LED current. This provides
an 8.33:1 dynamic range of the dc dimming.
A low pass filter on the CTRL pin of the AP8802 automatically provides some soft-start function of the LED current on initial start-up (this
phenomenon can be seen in figure 7); the built in soft-start period can be increased by the addition of an external capacitor onto the CTRL
pin.
The AP8802’s dimming range can be increased above this DC dimming factor by applying a PWM signal to the CTRL pin using this method
dimming dynamic ranges above 100 can be achieved.
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Application Information (cont.)
PWM Dimming of LED Current
When a low frequency PWM signal with voltages between 2.5V and a low level of zero is applied to the CTRL pin the output current will be
switched on and off at the PWM frequency. The resultant LED current ILEDavg will be proportional to the PWM duty cycle. See Figure 20.
A Pulse Width Modulated (PWM) signal with a max resolution of 8-bit, can be applied to the CTRL pin to change the output current to a value
above or below the nominal average value set by resistor RSET.
To achieve this resolution the PWM frequency has to be lower than 500Hz. The ultimate resolution will be determined by the number of
switching cycles required to get back to nominal LED current once the PWM voltage is high relative to PWM frequency. Lower switching
frequencies and higher PWM frequencies will result in lower PWM dimming dynamic ranges.
Figure 20. Low Frequency PWM Operating Waveforms
There are different ways of accomplishing PWM dimming of the AP8802 LED current:
Directly Driving CTRL Input
A Pulse Width Modulated (PWM) signal with duty cycle DPWM can be applied to the CTRL pin to adjust the output current to a value above or
below the nominal average value set by resistor RSET. When driving the CTRL with a voltage waveform care should be taken not to exceed a
drive voltage of 2.5V (where extra brightness is required) or 1.25V if a maximum of 100% brightness is required.
A way of avoiding over-driving the CTRL pin is use an open collector/drain driver to drive the CTRL pin.
Driving the CTRL Input via Open Collector Transistor
The recommended method of driving the CTRL pin and controlling the amplitude of the PWM waveform is to use a small NPN switching
transistor. This uses the internal pull-up resistor between the CTRL pin and the internal voltage reference to pull-up CTRL pin when the
external transistor is turned off.
Driving the CTRL Input From a Microcontroller
If the CTRL pin is driven by a MOSFET (either discrete or open-drain output of a micro-controller) then Schottky diode maybe be required due
to high Gate / Drain capacitance, which could inject a negative spike into CTRL input of the AP8802 and cause erratic operation but the
addition of a Schottky clamp diode (eg Diodes Inc. SD103CWS) to ground and inclusion of a series resistor (3.3k) will prevent this.
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Application Information (cont.)
Soft-Start
An external capacitor from the CTRL pin to ground will provide a soft-start delay, by increasing the time taken for the voltage on this pin 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 capacitance
increases this delay by approximately 200µs/nF. The graph below shows the variation of soft-start time for different values of capacitor.
16
SOFT-START TIME (ms)
14
12
10
8
6
4
2
0
-2
0
20
40
60
80
100
120
CAPACITANCE (nF)
Figure. 21 Soft-Start Time vs. Capacitance
from ADJ Pin to Ground
Thermal Considerations
The graph below in Figure 22, gives details for power derating. This assumes the device to be mounted on a 25x25mm PCB with 1oz copper
standing in still air.
2.6
2.4
POWER DISSIPATION (W)
2.2
U-DFN3030-10
2.0
1.8
1.6
SO-8EP
1.4
1.2
1.0
SO-8
0.8
0.6
0.4
0.2
0.0
0
AP8802
Document number: DS31766 Rev. 9 - 2
25
50
75
100
AMBIENT TEMPERATURE (°C)
Maximum Power Dissipation
Figure. 22 AP8802 Derating Curves
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AP8802
1A LED STEP-DOWN CONVERTER
Application Information (cont.)
Package Selection
The device comes with a wide selection of packages. The suggested package is able to provide a case temperature below 70°C (with an
ambient temperature of +25°C) for the combination of input voltage and load requested.
12 LEDs
11 LEDs
10 LEDs
9 LEDs
8 LEDs
7 LEDs
6 LEDs
5 LEDs
4 LEDs
3 LEDs
2 LEDs
1 LED
8
10
12
14
16
18
20
22
24
26
28 30 32 34 36 38 40 42
VIN
Figure. 22 Suggested Package @ ILED = 1A and 100µH Inductor
44 46
48
12 LEDs
11 LEDs
10 LEDs
9 LEDs
8 LEDs
7 LEDs
6 LEDs
5 LEDs
4 LEDs
3 LEDs
2 LEDs
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40
42
44
46
1 LED
48
VIN
Figure. 23 Suggested Package @ ILED = 700mA and 100µH Inductor
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Applications Information (cont.)
Fault Condition Operation
The AP8802 has by default open LED protection. If the LEDs should become open circuit the AP8802 will stop oscillating; the SET pin will
rise to VIN and the SW pin will then fall to GND. No excessive voltages will be seen by the AP8802.
If the LEDs should become shorted together the AP8802 will continue to switch however the duty cycle at which it will operate will change
dramatically and the switching frequency will most likely decrease. The on-time of the internal power MOSFET switch will be significantly
reduced because almost all of the input voltage is now developed across the inductor. The off-time will be significantly increased because the
reverse voltage across the inductor is now just the Schottky diode voltage (See Figure 20) causing a much slower decay in inductor current.
During this condition the inductor current will remain within its controlled levels and so no excessive heat will be generated within the
AP8802.
Figure. 24 Switching Characteristics (normal open to short LED chain)
AP8802
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AP8802
1A LED STEP-DOWN CONVERTER
Ordering Information
AP 8802 XX G - X
Package
S : SO-8
SP : SO-8EP
FN : U-DFN3030-10
Device
Package Code
Green
Packing
G : Green
7/ 13 : Tape & Reel
7”/13” Tape and Reel
Packaging
(Note 11)
Quantity
Part Number Suffix
AP8802SG-13
S
SO-8
2500/Tape & Reel
-13
AP8802SPG-13
SP
SO-8EP
2500/Tape & Reel
-13
AP8802FNG-7
FN
U-DFN3030-10
3000/Tape & Reel
-7
Notes:
11. 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
(1) SO-8
( Top View )
8
Logo
Part Number
5
AP8802
YY WW X X
1
G : Green
YY : Year : 08, 09,10~
WW : Week : 01~52; 52
represents 52 and 53 week
X : Internal Code
4
(2) SO-8EP
( Top View )
8
5
Logo
Part No.
AP8802
YY WW X X E
1
AP8802
Document number: DS31766 Rev. 9 - 2
G : Green
YY : Year : 08, 09,10~
WW : Week : 01~52; 52
represents 52 and 53 week
X : Internal Code
SOP-8L-EP
4
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AP8802
1A LED STEP-DOWN CONVERTER
Marking Information (cont.)
(3) U-DFN3030-10
( Top View )
XX : Identification Code
Y : Year : 0~9
W : Week : A~Z : 1~26 week;
a~z : 27~52 week; z represents
52 and 53 week
X : A~Z : Green
XX
YW X
Part Number
Package
Identification Code
AP8802FNG-7
U-DFN3030-10
A5
Package Outline Dimensions (All Dimensions in mm)
0.254
(1) Package Type: SO-8
E1 E
A1
L
Gauge Plane
Seating Plane
Detail ‘A’
7°~9°
h
45°
A2 A A3
Detail ‘A’
SO-8
Dim
Min
Max
A
1.75
A1
0.10
0.20
A2
1.30
1.50
A3
0.15
0.25
b
0.3
0.5
D
4.85
4.95
E
5.90
6.10
E1
3.85
3.95
e
1.27 Typ
h
0.35
L
0.62
0.82
0°
8°
θ
All Dimensions in mm
b
e
D
AP8802
Document number: DS31766 Rev. 9 - 2
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AP8802
1A LED STEP-DOWN CONVERTER
Package Outline Dimensions (cont.) (All Dimensions in mm)
(2) Package Type: SO-8EP
Exposed Pad
8
5
E1
1
H
4
F
b
Bottom View
E
9° (All sides)
N
7°
Q
C
4° ± 3°
A
e
Gauge Plane
Seating Plane
E0
A1
D
45°
L
SO-8EP (SOP-8L-EP)
Dim Min Max Typ
A 1.40 1.50 1.45
A1 0.00 0.13
b 0.30 0.50 0.40
C 0.15 0.25 0.20
D 4.85 4.95 4.90
E 3.80 3.90 3.85
E0 3.85 3.95 3.90
E1 5.90 6.10 6.00
e
1.27
F 2.75 3.35 3.05
H 2.11 2.71 2.41
L 0.62 0.82 0.72
N
0.35
Q 0.60 0.70 0.65
All Dimensions in mm
(3) Package Type: U-DFN3030-10
A3
A
SEATING PLANE
A1
D
D2
Pin#1 ID
E E2
L
z
e
AP8802
Document number: DS31766 Rev. 9 - 2
U-DFN3030-10
Dim Min Max Typ
A
0.57 0.63 0.60
A1
0
0.05 0.02
A3
0.15
⎯
⎯
b
0.20 0.30 0.25
D
2.90 3.10 3.00
D2 2.30 2.50 2.40
e
0.50
⎯
⎯
E
2.90 3.10 3.00
E2
1.50 1.70 1.60
L
0.25 0.55 0.40
z
⎯
⎯ 0.375
All Dimensions in mm
b
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AP8802
1A LED STEP-DOWN CONVERTER
Suggested Pad Layout
(1) Package Type: SO-8
X
Dimensions
X
Y
C1
C2
Value (in mm)
0.60
1.55
5.4
1.27
C1
C2
Y
(2) Package Type: SO-8EP
2
X
Dimensions
2
Y
1
Y
C
X
X1
X2
Y
Y1
Y2
1
X
Value
(in mm)
1.270
0.802
3.502
4.612
1.505
2.613
6.500
Y
X
C
(3) Package Type: U-DFN3030-10
Y
C
X1
G
X
G
Dimensions Value (in mm)
Z
2.60
G
0.15
X
1.80
X1
0.60
Y
0.30
C
0.50
Z
AP8802
Document number: DS31766 Rev. 9 - 2
18 of 19
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© Diodes Incorporated
AP8802
1A LED STEP-DOWN CONVERTER
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).
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 © 2012, Diodes Incorporated
www.diodes.com
AP8802
Document number: DS31766 Rev. 9 - 2
19 of 19
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May 2012
© Diodes Incorporated