AW36518
Oct. 2018 V1.0
High Efficiency, Independent 1.5A Flash LED Driver
Features
General Description
1.5A Accurate and Programmable LED Current
Source
Flash：2.94mA~1.5A，256 levels
5.88mA/level
Torch： 0.75mA~386mA，256 levels
1.51mA/level
Flash Timeout：40ms~1.6s，16 levels
Flash/Torch/IR Mode
The AW36518 is a LED flash driver that provides a
high level of adjustability within a small solution
size. The AW36518 utilizes a 2MHz or 4MHz
fixed-frequency synchronous boost converter to
provide power to the 1.5A constant current LED
sources. The 256 levels current sources provide
the flexibility to adjust the current of LED in
Flash/Torch/IR modes. The AW36518 provides
IVFM protection to prevent system reset or
shutdown under low battery condition.
Up to 85% Flash Efficiency
Optimized Flash LED Current During Low Battery
Conditions (IVFM)
The AW36518 are controlled via an I2C compatible interface. The main features of the
AW36518 include: flash/torch current, flash timeout
duration, IVFM and TX interrupt. The AW36518
also
provides
hardware
flash/torch
pin
(STROBE/TORCH) to control Flash/Torch events.
Hardware Flash/Torch Enable (STROBE/TORCH)
Synchronization Input for RF Power Amplifier
Pulse Events (TX)
400kHz I2C：AW36518 (I2C Address=0x63)
0.4mm Pitch，FCQFN-10L Package
Compatible with AW3648
The 2MHz or 4MHz switching frequency options,
overvoltage protection (OVP), and adjustable
current limit allow for the use of tiny, low-profile
inductors and 10-µF ceramic capacitors. The
device operates over a –40°C to +85°C ambient
temperature range.
Application
Smartphone Camera Flash
The AW36518 is available in small 0.4mm pitch
FCQFN 1.6mm×1.2mm -10L package.
Typical Application Circuit
L 1μH 3A
VIN
CIN
10μF
IN
SW
OUT
COUT
10μF
AW36518FCR
STROBE/TORCH
TX
SDA
SCL
MCU
LED
Flash
LED
D
GND
Typical Application Circuit of AW36518
All trademarks are the property of their respective owners.
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1
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Pin Configuration And Top Mark
AW36518FCR Pin Configuration
(Top View)
A
GND
B
SW
SCL
C
OUT
STROBE/
TORCH
D
LED
TX
LED
1
2
3
IN
AW36518FCR Top Mark
(Top View)
SDA
LGW6
XXX
LGW6 – AW36518FCR
XXX – Production Tracing Code
Pin Configuration and Top Mark
Pin Definition
No.
NAME
TYPE
A1
GND
Ground
Ground
A2
IN
Power
Input voltage connection. Connect IN to GND with a 10µF or larger
ceramic capacitor.
A3
SDA
I/O
Serial data input/output of the I2C interface.
B1
SW
Power
Switch pin of the step-up DC-DC convertor.
B3
SCL
I/O
C1
OUT
Power
Step-up DC-DC converter output. Connect a 10µF ceramic
capacitor between OUT and GND.
C3
STROBE/TORCH
I/O
Active high hardware flash/torch/IR enable. Drive STROBE/TORCH
high to turn on Flash/Torch/IR pulse. Internal pull down resistor of
300kΩ between STROBE/TORCH and GND.
D1
LED
Power
High-side current source output for flash LED, connect pin D1 to D3
externally
D2
TX
I/O
Power amplifier synchronization input. Internal pull down resistor of
300kΩ between TX and GND.
D3
LED
Power
High-side current source output for flash LED, connect pin D1 to D3
externally.
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DESCRIPTION
Serial clock input of the I2C interface.
2
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Ordering Information
Part Number
Temperature
Package
Marking
Moisture
Sensitivity
Level
Environmental
Information
Delivery
Form
AW36518FCR
-40°C~85°C
FCQFN
1.6mmX1.2mm
-10L
LGW6
MSL1
ROHS+HF
3000 units/
Tape and Reel
AWINIC Flash LED Driver Series
Product
Channels
Type
Description
Package
AW36515
2
Boost
High Efficiency, Dual Independent 2A Flash LED Driver
FCQFN-10L
AW3644
2
Boost
High Efficiency, Dual Independent 1.5A Flash LED
Driver
CSP-12B
AW3643
2
Boost
High Efficiency, Dual 1.5A Flash LED Driver
CSP-12B
AW36413
2
Boost
High Efficiency, Dual 1.5A Flash LED Driver
CSP-12B
AW3648
1
Boost
High Efficiency, 1.5A Flash LED Driver
CSP-12B
AW3642
1
Boost
High Efficiency, 1.5A Flash LED Driver
CSP-9B
AW3641E
1
Charge
Pump
Flash Current & Flash Timer Programmable 1A Flash
LED Driver
DFN-10L
AW36402
1
Current
Sink
200mA 1-wire Configurable Front Flash LED Driver
with Ultra Small Package
DFN-6L
AW36404
1
Current
Sink
400mA 1-wire Configurable Front Flash LED Driver
with Ultra Small Package
DFN-8L
AW36406
1
Current
Sink
600mA PWM Configurable Front Flash LED Driver
with Ultra Small Package
DFN-8L
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3
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Typical Application Circuits
L 1μH 3A
VIN
CIN
10μF
IN
SW
OUT
COUT
10μF
AW36518FCR
STROBE/TORCH
TX
SDA
SCL
MCU
LED
Flash
LED
D
GND
AW36518 Application Circuit
Notice for Typical Application Circuits:
1:
Please place CIN，COUT as close to the chip as possible.
2:
Connect the inductor on the top layer close to the SW pin.
3: For the sake of driving capability, the power lines, output lines, and the connection lines of L and LED
should be short and wide as possible.
4:
Traces carry high current are marked in red in the above figure.
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4
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Absolute Maximum Ratings(NOTE1)
PARAMETERS
Range
Unit
-0.3 to 6
V
SCL, SDA, STROBE/TORCH, TX
−0.3 to (VIN+0.3)
V
Continuous power dissipation
Internally limited
IN, SW, OUT, LED
Max Junction Temperature TJMAX
155
°C
-65 to 150
°C
Maximum lead temperature (soldering)
260
°C
Junction to Ambient Thermal Resistance θJA
90.2
°C /W
HBM
±2000
V
CDM
±1500
V
Storage Temperature TSTG
ESD, All Pins(NOTE2)
+IT：+200
Latch-Up (Test method: JEDEC STANDARD NO.78D)
-IT： -200
mA
Recommended Operating Conditions
PARAMETERS
Range
Unit
VIN
2.7 to 5.5
V
Junction temperature (TJ)
-40 to 125
°C
Ambient temperature (TA)
-40 to 85
°C
NOTE1: Conditions out of those ranges listed in "absolute maximum ratings" may cause permanent damages
to the device. In spite of the limits above, functional operation conditions of the device should within the
ranges listed in "recommended operating conditions". Exposure to absolute-maximum-rated conditions for
prolonged periods may affect device reliability.
NOTE2: The human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. Test
method: ANSI/ESDA/JEDEC JS-001. CDM test method: JEDEC22-C101E.
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Electrical Characteristics
Typical values tested at TA=25°C. Minimum and maximum limits apply over the full operating ambient
temperature range(-40°C≤TA≤85°C). Unless otherwise specified, VIN=3.6V.
Symbol
Description
Test Condition
Min
Typ
Max
Unit
5.5
V
0.4
0.8
mA
3
10
A
Vin Supply
VIN
Input operating range
2.7
IQ
Quiescent supply current
Device not switching, pass mode
ISB
Standby supply current
Device disabled,
2.7V≤VIN≤5.5V,SCL=SDA=0V
UVLO
Under voltage lockout
threshold
Falling VIN
2.5
V
Rising VIN
2.6
V
Current Source Specifications
ILED1/2
VOVP
VOUT=4V,
flash code=0xFF=1.5A
-7%
1.5
7%
A
VOUT=4V,
torch code=0x7F=192.7mA
-10%
192.7
10%
mA
ON threshold
4.85
5
5.15
OFF threshold
4.75
4.9
5.05
Current source accuracy
VOUT over-voltage protect
threshold
V
Boost Converter Specifications
RPMOS
PMOS switch on-resistance
90
mΩ
RNMOS
NMOS switch on-resistance
70
mΩ
ICL
Switch current limit
FSW
VIVFM
Reg 0x07, bit[0]=0
-12%
1.9
12%
Reg 0x07, bit[0]=1
-12%
2.8
12%
Reg 0x07, bit[1]=0
-6%
2
6%
Reg 0x07, bit[1]=1
-6%
4
6%
Reg 0x02, bits[5:3]=”000”
-3%
2.9
3%
A
Switching frequency
Input voltage flash monitor
trip threshold
MHz
Thermal shutdown threshold
155
Thermal shutdown hysteresis
20
TSD
V
°C
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Electrical Characteristics(continued)
Typical values tested at TA=25°C. Minimum and maximum limits apply over the full operating ambient
temperature range(-40°C≤TA≤85°C). Unless otherwise specified, VIN=3.6V.
Symbol
Description
Test Condition
Min
Typ
Max
Unit
I2C-Compatible Interface Specifications(SCL,SDA)
VIL
Input logic low
0
0.4
V
VIH
Input logic high
1.2
VIN
V
VOL
Output logic low
0.4
V
ILOAD=3mA
STROBE/TORCH, TX Voltage Specifications
VIL
Input logic low
0
0.4
V
VIH
Input logic high
1.2
VIN
V
RPD
Internal pull down resistors
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300
7
kΩ
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
I2C Interface Timing
Symbol
Min
Description
FSCL
Interface Clock frequency
TDEGLITCH
Deglitch time
Typ
Max
Units
400
kHz
SCL
200
ns
SDA
250
ns
THD:STA
(Repeat-start) Start condition hold time
0.6
s
TLOW
Low level width of SCL
1.3
s
THIGH
High level width of SCL
0.6
s
TSU:STA
(Repeat-start) Start condition setup time
0.6
s
THD:DAT
Data hold time
0
s
TSU:DAT
Data setup time
0.1
s
TR
Rising time of SDA and SCL
0.3
s
TF
Falling time of SDA and SCL
0.3
s
TSU:STO
Stop condition setup time
0.6
s
TBUF
Time between start and stop condition
1.3
s
VIH
SDA
VIL
tBUF
tLOW
tHIGH
tR
tSP
tF
VIH
SCL
VIL
Stop
Start
tHD:STA
tHD:DAT
tSU:DAT
tSU:STA
Start
tSU:STO
Stop
I2C INTERFACE TIMING
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Typical Characteristics
Ambient temperature is 25°C, input voltage is 3.6 V, CIN = COUT = 2×10 µF and L=1 µH, unless otherwise
noted .
1.6
0.4
1.4
0.36
0.32
1.2
0.28
ILED1 (A)
ILED (A)
1
0.8
0.6
0.2
0.16
0.12
0.4
0.08
0.2
0.04
0
0
0
32
64
96
128
160
192
224
256
0
96
128
160
192
224
LED Flash Current vs Brightness Code
LED Torch Current vs Brightness Code
1.60
1.58
1.58
1.56
1.56
1.54
1.54
1.52
1.52
1.50
1.48
1.48
1.46
1.44
1.44
1.42
1.42
3
3.5
4
4.5
VIN (V)
fSW=2MHz
ILED=1.5A
5
256
1.50
1.46
1.40
1.40
5.5
2.5
Flash
3
3.5
4
4.5
VIN (V)
fSW=4MHz
ILED=1.5A
LED Flash Current vs Input Voltage
5
5.5
Flash
LED Flash Current vs Input Voltage
1.10
1.10
1.08
1.08
1.06
1.06
1.04
1.04
1.02
1.02
ILED (A)
ILED (A)
64
LED Torch Code (dec#)
1.60
2.5
32
LED Flash Code (dec#)
ILED (A)
ILED (A)
0.24
1.00
0.98
1.00
0.98
0.96
0.96
0.94
0.94
0.92
0.92
0.90
0.90
2.5
3
ILED=1.0A
3.5
4
VIN (V)
fSW=2MHz
4.5
5
Flash
LED Flash Current vs Input Voltage
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9
5.5
2.5
3
ILED=1.0A
3.5
4
VIN (V)
fSW=4MHz
4.5
5
5.5
Flash
LED Flash Current vs Input Voltage
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Typical Characteristics (continued)
Ambient temperature is 25°C, input voltage is 3.6 V, CIN = COUT = 2×10 µF and L=1 µH, unless otherwise
noted .
0.87
0.60
0.85
0.58
0.83
0.56
0.54
0.79
ILED (A)
ILED (A)
0.81
0.77
0.75
0.52
0.50
0.48
0.73
0.71
0.46
0.69
0.44
0.67
0.42
2.5
3
3.5
4
4.5
VIN (V)
fSW=2MHz
ILED=0.749A
5
5.5
2.5
Flash
0.43
0.42
0.42
0.41
0.41
0.4
ILED (A)
ILED (A)
0.44
0.43
0.39
0.38
0.36
0.35
0.35
0.34
ILED=0.386A
VIN(V)
fsw=2MHz
5
2.5
Torch
0.22
0.21
0.21
0.2
ILED (A)
ILED (A)
0.22
0.19
0.18
0.16
0.15
ILED=0.192A
VIN(V)
fsw=2MHz
Torch
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5.5
10
5.5
Torch
0.15
2.5
3
3.5
ILED=0.192A
LED1/2 Torch Current vs Input Voltage
5
0.18
0.16
5
4.5
0.2
0.17
4.5
4
VIN(V)
fsw=4MHz
0.19
0.17
4
3.5
LED1/2 Torch Current vs Input Voltage
0.23
3.5
3
ILED=0.386A
0.23
3
Flash
0.34
5.5
LED1/2 Torch Current vs Input Voltage
2.5
5.5
0.38
0.37
4.5
5
0.4
0.36
4
4.5
0.39
0.37
3.5
4
VIN (V)
fSW=2MHz
LED Flash Current vs Input Voltage
0.44
3
3.5
ILED=0.502A
LED Flash Current vs Input Voltage
2.5
3
4
4.5
VIN(V)
fsw=4MHz
5
5.5
Torch
LED1/2 Torch Current vs Input Voltage
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Typical Characteristics (continued)
Ambient temperature is 25°C, input voltage is 3.6 V, CIN = COUT = 2×10 µF and L=1 µH, unless otherwise
noted .
100
95
VLED=3.5V
90
VLED=3.8V
95
VLED=3.1V
90
VLED=4.1V
85
85
VLED=4.4V
80
ηLED (%)
ηLED (%)
100
VLED=3.3V
75
70
80
75
70
65
65
60
60
55
55
50
2.5
3.0
3.5
ILED=1.5A
4.0
4.5
5.0
VIN (V)
fSW=2Mhz
Flash
50
5.5
2.5
ILED=1.5A
100
100
95
95
90
90
85
85
80
80
75
70
65
60
55
55
50
ILED=1.0A
4.0
4.5
VIN (V)
VLED=3.2V
fSW=2MHz
5.0
2.5
Flash
95
90
90
85
85
80
80
ηLED (%)
ηLED (%)
100
75
70
65
60
55
55
50
ILED=0.386A
5.0
VIN (V)
VLED=2.9V
fSW=2MHz
5.5
Torch
LED Efficiency vs Input Voltage
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3.5
4.0
4.5
VIN (V)
VLED=3.2V
fSW=4MHz
5.0
5.5
Flash
70
60
4.5
Flash
75
65
4.0
5.5
LED Efficiency vs Input Voltage
95
3.5
3.0
ILED=1.0A
100
3.0
5.0
50
5.5
LED Efficiency vs Input Voltage
2.5
4.5
70
60
3.5
4.0
VIN (V)
VLED=3.5V
fSW=2Mhz
75
65
3.0
3.5
LED Efficiency vs Input Voltage
ηLED (%)
ηLED (%)
LED Efficiency vs Input Voltage
2.5
3.0
11
50
2.5
3.0
ILED=0.192A
3.5
4.0
4.5
5.0
VIN (V)
VLED=2.75V
fSW=2MHz
5.5
Torch
LED Efficiency vs Input Voltage
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Typical Characteristics (continued)
2.150
4.300
2.125
4.250
2.100
4.200
2.075
4.150
2.050
4.100
fSW (Mhz)
fSW (Mhz)
Ambient temperature is 25°C, input voltage is 3.6 V, CIN = COUT = 2×10 µF and L=1 µH, unless otherwise
noted .
2.025
2.000
4.000
1.975
3.950
1.950
3.900
1.925
3.850
1.900
3.800
2.5 2.75
3
3.25 3.5 3.75
4
4.25 4.5 4.75
5
2.5 2.75
3
3.25 3.5 3.75
4
4.25 4.5 4.75
VIN (V)
VIN (V)
2-MHz Frequency vs Input Voltage
4-MHz Frequency vs Input Voltage
3.0
7
2.5
6
5
5
ISTB (μA)
2.0
ISTB (μA)
4.050
1.5
1.0
4
3
2
0.5
1
0.0
2.5
3
3.5
4
4.5
5
0
5.5
2.5
3
3.5
4
4.5
5
VIN (V)
I2C=0V
VIN (V)
I2C=1.8V
Standby Current vs Input Voltage
Standby Current vs Input Voltage
5
5.5
3.0
2.5
4
ISTB (μA)
ISTB (μA)
2.0
3
2
1.5
1.0
1
0.5
0
0.0
2.5
3
3.5
4
4.5
5
5.5
2.5
3
3.5
4
4.5
5
VIN (V)
I2C=3.3V
VIN (V)
I2C=VIN
Standby Current vs Input Voltage
Standby Current vs Input Voltage
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5.5
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Typical Characteristics (continued)
2.20
2.16
2.12
2.08
2.04
2.00
1.96
1.92
1.88
1.84
1.80
1.76
1.72
1.68
1.64
1.60
ICL (A)
ICL (A)
Ambient temperature is 25°C, input voltage is 3.6 V, CIN = COUT = 2×10 µF and L=1 µH, unless otherwise
noted .
2.5
2.7
2.9
3.1
3.3
3.5
VIN (V)
fSW=2MHz
ICL=1.9A
ILED=1.5A
3.7
3.9
4.1
2.20
2.16
2.12
2.08
2.04
2.00
1.96
1.92
1.88
1.84
1.80
1.76
1.72
1.68
1.64
1.60
4.3
2.5
VLED=4.5V
2.9
3.1
3.3
3.5
VIN (V)
fSW=4MHz
ICL=1.9A
ILED=1.5A
Inductor Current Limit vs Input Voltage
3.7
3.9
4.1
4.3
VLED=4.5V
Inductor Current Limit vs Input Voltage
3.0
3.0
2.8
2.8
2.6
2.6
2.4
2.4
ICL (A)
ICL (A)
2.7
2.2
2.2
2.0
2.0
1.8
1.8
1.6
1.6
1.4
1.4
2.5
2.8
3.1
ILED=1.5A
3.4
3.7
VIN (V)
fSW=2MHz
ICL=2.8A
4
4.3
4.6
4.9
2.5
ILED(500mA/DIV)
fSW=2MHz
4
4.3
4.6
4.9
VLED=4.5V
IIN(1A/DIV)
ILED(500mA/DIV)
TIME (500 μs/DIV)
VLED=3.4V
Ramp Up
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3.7
VIN (V)
fSW=4MHz
ICL=2.8A
VOUT(2V/DIV)
TIME (500 μs/DIV)
ILED=1.5A
3.4
Inductor Current Limit vs Input Voltage
Inductor Current Limit vs Input Voltage
IIN(1A/DIV)
3.1
ILED=1.5A
VLED=4.5V
VOUT(2V/DIV)
2.8
ILED=1.5A
fSW=2MHz
VLED=3.4V
Ramp Down
13
Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Typical Characteristics (continued)
Ambient temperature is 25°C, input voltage is 3.6 V, CIN = COUT = 2×10 µF and L=1 µH, unless otherwise
noted .
VIN (100mV/DIV)
TX signal
VOUT(2V/DIV)
IIN (500mA/DIV)
IIN(800mA/DIV)
ILED (200mA/DIV)
ILED(500mA/DIV)
TIME (500 μs/DIV)
TIME (2 ms/DIV)
ILED=1.5A
fSW=2MHz
VLED=3.18V
fSW=2MHz
VLED=3.18V
VIVFM=2.9V
IVFM - Stop and Hold
TX Interrupt
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ILED=1.5A
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Detailed Functional Description
The AW36518 is a high-power LED flash driver capable of delivering up to 1.5A in either of the LED. The
device incorporates a 2MHz or 4MHz constant frequency-synchronous current-mode PWM boost converter
and dual high-side current sources to regulate the LED current over the 2.7V to 5.5V input voltage range.
The AW36518 PWM DC-DC boost converter switches and boosts the output to maintain at least VHR across
the current source. This minimum headroom voltage ensures that current source remains in regulation. If the
input voltage is above the LED voltage + current source headroom voltage, the device would not switch, but
turn the PMOS on continuously (Pass mode). In Pass mode the difference between (V IN − ILED × RPMOS) and
the voltage across the LED is dropped across the current source.
The AW36518 has two logic inputs including a reusable hardware Flash/Torch Enable (STROBE/TORCH)
and a Flash Interrupt input (TX) designed to interrupt the flash pulse during high battery-current conditions.
These logic inputs have internal 300kΩ (typical) pull-down resistors to GND.
Control is done via an I2C-compatible interface. This includes adjustment of the Flash and Torch current
levels, changing the Flash Timeout Duration, and changing the switch current limit. Additionally, there are flag
and status bits that indicate flash current timeout, LED over-temperature condition, LED failure (open/short),
device thermal shutdown, TX interrupt, and VIN under-voltage conditions.
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AW36518
Oct. 2018 V1.0
Functional Block Diagram
SW
AW36518
OVP
IN
Thermal Shutdown
Protection
UVLO
POR
VOVP
IVFM
OSC
2/4MHz
OUT
Boost Controller
Current
Limit
LED
STROBE/TORCH
TX
SDA
SCL
Control Logic
/Regsiter
2
IC
Interface
LED & OUT
Short Detect
GND
Features Description
Power On Reset
When the supply voltage VIN drops below a predefined voltage VPOR (2.0V typical), the device generates a
reset signal to perform a power-on reset operation, which will reset all control circuits and configuration
registers.
Once VIN goes above around VPOR (2.0V typical), it should stay high for at least 2ms time before any I2C
command can be accepted.
Software Reset
By setting bit[7](Software Reset Bit) to a ‘1’ in the Boost Configuration Register(0x07) via I 2C interface will
reset the AW36518 internal circuit and all configuration registers, after the soft reset command is input
through I2C, it needs to wait at least 2ms before any other I2C command can be accepted.
Flash Mode
In Flash Mode, the LED current source provides 256 target current levels from 2.94mA to 1.5A. The Flash
currents are adjusted via the LED Flash Brightness Registers. Flash mode is activated by the Enable
Register(setting M1, M0 to '11'), or by pulling the STROBE/TORCH pin HIGH when bit[5] (Strobe Enable Bit)
is ‘1’ in the Enable Register(0x01). Once the Flash sequence is activated the current source ramps up to the
programmed Flash current by stepping through all current steps until the programmed current is reached.
When the device is enabled in Flash Mode through the Enable Register, all mode bits in the Enable Register
are cleared after a flash timeout event.
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Torch Mode
In Torch mode, the LED current source provides 256 target current levels from 0.75mA to 386mA on
AW36518. The Torch currents are adjusted via the LED Torch Brightness Register. Torch mode is activated
by the Enable Register (setting M1, M0 to '10'), or by pulling the STROBE/TORCH pin HIGH when bit[5]
(Torch Enable Bit) is ‘1’ in the Enable Register(0x01). Once the TORCH sequence is activated the active
current source ramps up to the programmed Torch current by stepping through all current steps until the
programmed current is reached. The rate at which the current ramps is determined by the value chosen in the
Timing Register.
AW36518 will execute flash operation when both bit[4] and bit[5] are ‘1’ in the Enable Register with pulling the
STROBE/TORCH pin HIGH.
Torch Mode is not affected by Flash Timeout or by a TX Interrupt event.
IR Mode
In IR Mode, Enable register bit[3:2] should be to ‘01’ (setting M1, M0 to '01') and the STROBE/TORCH pin
should be enabled(Strobe Enable Bit). The target LED current is equal to the value stored in the LED Flash
Brightness Registers. When IR mode is enabled, the boost converter turns on and set the output equal to the
input (pass-mode) . The STROBE/TORCH pin can only be set to be Level sensitive, meaning all timing of the
IR pulse is externally controlled, but it is still protected by flash time-out if STROBE width is too long. In IR
Mode, the current sources do not ramp the LED output to the target. LED is enabled to the full current setting
without delay or slow ramp during STROBE rising edge, and they are fully turned off immediately without
delay or slow ramp during STROBE falling edge
BOOST
VOUT
PASS
OFF
STROBE
ILED
M1,M0=‘01’
STROBE EN=‘1’
M1,M0=‘00’
STROBE EN=‘1’
IR Mode with Boost
VOUT
STROBE
ILED
M1,M0=‘00’
STROBE EN=‘1’
M1,M0=‘01’
STROBE EN=‘1’
IR Mode Pass Only
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
VOUT
STROBE
Flash Timeout Value
ILED
M1,M0=‘01’ Timeout
Start
Timeout
STROBE EN=‘1’
Reset
Timeout
Start Timeout
Reset
Timeout
Start
Timeout Reached
VOUT goes low，
LED turn off
IR Mode Timeout
Soft Start-up
Turn on the AW36518 Torch and Flash modes can be done through the Enable Register. On start-up, when
VOUT is less than VIN the internal synchronous PMOS turns on as a current source and delivers 200mA (typical)
to the output capacitor. During this time the current source (LED) is off. When the voltage across the output
capacitor reaches 2.2 V (typical) the current source turns on. At turn-on the current source steps through each
FLASH or TORCH level until the target LED current is reached. This gives the device a controlled turn-on and
limits inrush current from the VIN supply.
Pass Mode
The AW36518 starts up in Pass Mode and stays there until Boost Mode is needed to maintain regulation. In
Pass Mode the boost converter does not switch, and the synchronous PMOS turns fully on bringing VOUT up to
VIN − ILED × RPMOS. In Pass Mode the inductor current is not limited by the peak current limit. If the voltage
difference between VOUT and VLED falls below VHR, the device switches to Boost Mode.
By setting bit[2](BOOST MODE) to a ‘1’ in the Boost Configuration Register(0x07), the AW36518 will stay in
the Pass Mode regardless of the effects of VHR.
Power Amplifier Synchronization (TX)
The TX pin is a Power Amplifier Synchronization input. This is designed to reduce the flash LED current and
thus limit the battery current during high battery current conditions such as PA transmit events. When the
AW36518 is engaged in a Flash event, and the TX pin is pulled high, the LED current is forced into Torch
Mode at the programmed Torch current setting. If the TX pin is then pulled low before the Flash pulse
terminates, the LED current returns to the previous Flash current level. At the end of the Flash time-out,
whether the TX pin is high or low, the LED current turns off.
The TX input can be disable by setting bit[7] (TX Enable) to a ‘0’ in the Enable Register(0x01).
Input Voltage Flash Monitor (IVFM)
The AW36518 has the ability to adjust the flash current based upon the voltage level present at the IN pin
utilizing the Input Voltage Flash Monitor (IVFM). The adjustable threshold ranges from 2.9 V to 3.6 V in
100mV steps as well as adjustable hysteresis, with Stop-and-Hold mode. The IVFM threshold and hysteresis
are controlled by bits[5:3] and bit[2] respectively, in the IVFM Register(0x02). The Flags2 Register has the
IVFM flag bit set when the input voltage crosses the IVFM threshold value. Additionally, the IVFM threshold
sets the input voltage boundary that forces the AW36518 to either stop ramping the flash current during
startup in Stop and Hold Mode.
Stop and Hold Mode: Stops Current Ramp and holds the level for the remaining flash, If VIN falls below the
IVFM threshold value.
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AW36518
Oct. 2018 V1.0
Flash Event
VIN
T-Filter=4μs
IVFM-Threshold
Stop & Hold
Mode
Target Flash Current
Flash Current with
IVFM Disable
Flash Current
IVFM Mode
Flash Timeout
The Flash Timeout period sets the maximum time of one flash event, whether a flash stop command is
received or not. The AW36518 has 16 timeout levels ranging from 40ms to 1.6s (see TIMING
CONFIGURATION REGISTER (0X08) for more detail). Flash Timeout applies to both Flash and IR modes,
and it continues to count when the Flash mode is forced into Torch mode during a TX high event. The mode
bits are cleared and bit[0] is set in the Flags1 register(0x0A) upon a Flash Timeout. This fault flag can be reset
to '0' by reading back the Flags1 Register (0x0A), 'or by setting the SW RESET bit to a '1', or by removing
power to the AW36518.
Current Limit
When the inductor current limit is reached, the AW36518 terminates the charging phase of the switching cycle
until the next switching period. If the over-current condition persists, the device operates continuously in
current limit. The AW36518 features two selectable inductor current limits(1.9A and 2.8A) that are
programmable by bit[0] in Boost configuration Register(0x07).
Since the current limit is sensed in the NMOS switch, there is no mechanism to limit the current when the
device operates in Pass Mode (current does not flow through the NMOS in pass mode). The mode bits are
not cleared upon a Current Limit event, but a flag bit[3] is set in the Flags1 register(0x0A).
This fault flag can be reset to '0' by reading back the Flags1 Register (0x0A), or by setting the SW RESET bit
to a '1', or by removing power to the AW36518.
Undervoltage Lockout (UVLO)
The AW36518 has an internal comparator that monitors the voltage at IN and forces the AW36518 into
standby if the input voltage drops to 2.5 V. If the UVLO monitor threshold is tripped, the UVLO flag bit is set in
the Flags1 Register (0x0A). If the input voltage rises above 2.5 V, the AW36518 is not available for operation
until there is an I2C read of the Flags1 Register (0x0A). Upon a read, the Flags1 register is cleared, and
normal operation can resume if the input voltage is greater than 2.5 V.
VOUT Short Fault
The Output Short Fault flag reads back a '1' if the device is active in Flash or Torch mode and the boost output
experiences a short condition. VOUT short condition occurs if the voltage at OUT goes below 2.3V (typ.) while
the device is in Torch or Flash mode. There is a deglitch time of 2.048ms before the VOUT Short flag is valid.
The mode bits are cleared upon an the VOUT short fault. The AW36518 is not available for operation until
VOUT Fault flags is cleared. The VOUT Short Fault can be reset to '0' by reading back the Flags1 Register
(0x0A), or by setting the SW RESET bit to a '1', or by removing power to the AW36518.
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
LED Short Fault
The LED Short Fault flags read back a '1' if the device is active in Flash or Torch mode and either active LED
output experiences a short condition. An LED short condition is determined if the voltage at LED goes below
500mV (typ.) while the device is in Torch or Flash mode. There is a deglitch time of 256μs before the LED
Short Fault flag is valid. The mode bits are cleared upon an LED Short Fault. The AW36518 is not available
for operation until the LED Short Fault flags is cleared. The LED Short Faults can be reset to '0' by reading
back the Flags1 Register (0x0A), or by setting the SW RESET bit to a '1', or by removing power to the
AW36518.
Overvoltage Protection (OVP)
The output voltage is limited to typically 5 V. In situations such as an open LED, the AW36518 raises the
output voltage in order to try and keep the LED current at its target value. When VOUT reaches 5 V (typ.) the
overvoltage comparator trips and turns off the internal NMOS. When VOUT falls below the “VOVP Off
Threshold”, the AW36518 begins switching again. The mode bits are cleared, and the OVP Fault flag is set,
when an OVP condition is present for three rising OVP edges. This prevents momentary OVP events from
forcing the device to shut down. The AW36518 is not available for operation until the OVP Fault flag is cleared.
The OVP Fault can be reset to '0' by reading back the Flags2 Register (0x0A), or by setting the SW RESET bit
to a '1', or by removing power to the AW36518.
Thermal Shutdown (TSD)
When the AW36518 die temperature reaches 155°C, the thermal shutdown detection circuit trips, forcing the
AW36518 enter standby mode and writing a '1' to the Thermal Shutdown Fault flag of the Flags1 Register
(0x0A) . The AW36518 is only allowed to restart after the Thermal Shutdown Fault flag is cleared. The
Thermal Shutdown Faults can be reset to '0' by reading back the Flags1 Register (0x0A), or by setting the SW
RESET bit to a '1', or by removing power to the AW36518. Upon restart, if the die temperature is still above
155°C, the AW36518 resets the Fault flag and re-enters standby mode.
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Programming
Control Truth Table
MODE1
MODE0
STROBE EN
TORCH EN
STROBE/TORCH PIN
ACTION
0
0
0
0
X
Standby
0
0
0
1
Pos edge
Ext Torch
0
0
1
0
Pos edge
Ext Flash
0
0
1
1
Pos edge
Ext Flash
1
0
X
X
X
Int Torch
1
1
X
X
X
Int Flash
0
1
0
X
X
IRLED Standby
0
1
1
X
0
IRLED Standby
0
1
1
X
Pos edge
IRLED Enabled
I2C Interface
Data Validation
When SCL is high level, SDA level must be constant. SDA can be changed only when SCL is low level.
SDA
SCL
Data Line
Stable
Data Valid
Change
of Data
Allowed
Data Validation Diagram
I2C Start/Stop
I2C start: SDA changes from high level to low level when SCL is high level.
I2C stop: SDA changes from low level to high level when SCL is high level.
SDA
SCL
S/Sr
P
S: START condition
Sr: START Repeated condition
P: STOP condition
Start and Stop Conditions
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AW36518
Oct. 2018 V1.0
ACK (Acknowledgement)
ACK means the successful transfer of I2C bus data. After master sends an 8-bit data, SDA must be released;
SDA is pulled to GND by slave device when slave acknowledges.
When master reads, slave device sends 8-bit data, releases the SDA and waits for ACK from master. If ACK is
sent and I2C stop is not sent by master, slave device sends the next data. If ACK is not send by master, slave
device stops to send data and waits for I2C stop.
Data Output
by Transmiter
Not Acknowledge（NACK）
Data Output
by Receiver
Acknowledge（ACK）
2
1
SCL From
Master
8
9
Clock Pulse for
Acknowledgement
START
condition
I2C ACK Timing
Write Cycle
One data bit is transferred during each clock pulse. Data is sampled during the high state of the serial clock
(SCL). Consequently, throughout the clock’s high period, the data should remain stable. Any changes on the
SDA line during the high state of the SCL and in the middle of a transaction, aborts the current transaction.
New data should be sent during the low SCL state. This protocol allows a single data line to transfer both
command/control information and data using the synchronous serial clock.
Each data transaction is composed of a Start Condition, a number of byte transfers (set by the software) and
a Stop Condition to terminate the transaction. Every byte written to the SDA bus must be 8 bits long and is
transferred with the most significant bit first. After each byte, an Acknowledge signal must follow.
In a write process, the following steps should be followed:
a)
Master device generates START condition. The “START” signal is generated by lowering the
SDA signal while the SCL signal is high.
b)
Master device sends slave address (7-bit) and the data direction bit (R/W = 0).
c)
Slave device sends acknowledge signal if the slave address is correct.
d)
Master sends control register address (8-bit)
e)
Slave sends acknowledge signal
f)
Master sends data byte to be written to the addressed register
g)
Slave sends acknowledge signal
h)
If master will send further data bytes the control register address will be incremented by one after
acknowledge signal (repeat step f and g)
i)
Master generates STOP condition to indicate write cycle end
SCL
0
1
2
3
4
5
6
7
8
0
1
2
3
4
5
6
7
8
0
1
2
3
4
5
6
7
8
A6 A5 A4 A3 A2 A1 A0 R/WAck A7 A6 A5 A4 A3 A2 A1 A0 Ack D7 D6 D5 D4 D3 D2 D1 D0 Ack
SDA
Start
Device Address
Register Address
Write Data
Stop
I2C Write Timing
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Read Cycle
In a read cycle, the following steps should be followed:
a)
Master device generates START condition.
b)
Master device sends slave address (7-bit) and the data direction bit (R/W = 0).
c)
Slave device sends acknowledge signal if the slave address is correct.
d)
Master sends control register address (8-bit).
e)
Slave sends acknowledge signal.
f)
Master generates STOP condition followed with START condition or REPEAT START condition.
g)
Master device sends slave address (7-bit) and the data direction bit (R/W = 1).
h)
Slave device sends acknowledge signal if the slave address is correct.
i)
Slave sends data byte from addressed register.
j)
If the master device sends acknowledge signal, the slave device will increase the control register
address by one, then send the next data from the new addressed register.
k)
If the master device generates STOP condition, the read cycle is ended.
SCL
0
1
2
3
4
5
SDA
A6
A5
A4
A3
A2
A1
start
0
1
2
3
4
5
6
7
8
A0 R/W Ack A7
A6
A5
A4
A3
A2
A1
A0
Ack
6
7
8
Device Address
……
Using
Repeat start……
0
1
2
3
4
5
A6
A5
A4
A3
A2
A1
RS
6
7
8
0
A0 R/W Ack D7
……
S
1
...
6
D6 …… D1
7
8
D0 Ack
stop
Read Data
Device Address
Separated
Read/write
transaction ……
P
Register Address
0
1
2
3
4
5
A6
A5
A4
A3
A2
A1
6
7
8
0
A0 R/W Ack D7
Device Address
1
...
6
7
D6 …… D1
D0
Read Data
8
Ack
stop
I2C Read Timing
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AW36518
Oct. 2018 V1.0
Register Configuration
Register List
Register name
Address(HEX)
Read/Write
Default Value
Chip ID Register
0x00
Read
0x30
Enable Register
0x01
Read/Write
0x80
IVFM Register
0x02
Read/Write
0x01
LED Flash Brightness Register
0x03
Read/Write
0x7F
LED Torch Brightness Register
0x05
Read/Write
0x7F
Boost Configuration Register
0x07
Read/Write
0x09
Timing Configuration Register
0x08
Read/Write
0x1A
Flags1 Register
0x0A
Read
0x00
Flags2 Register
0x0B
Read
0x00
Device ID Register
0x0C
Read
0x0A
Last Flash Register
0x0D
Read
0x00
Register Detailed Description
Chip ID Register (0x00)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Chip ID: “00110000”
Enable Register (0x01)
Bit 7
TX Pin
Enable
0=Disabled
1=Enabled
(Default)
Bit 6
Strobe Type
0=Level
Triggered
(Default)
1=Edge
Triggered
Strobe
Enable
0=Disabled
(Default)
1=Enabled
Torch
Enable
0=Disabled
(Default)
1=Enabled
Mode Bits: M1, M0
00=Standby (Default)
01=IR Drive
10=Torch
11=Flash
LED2 Enable
00=OFF(Default)
11=ON
01 and 10 are not valid settings
Note:
In Edge or Level Strobe Mode, it is recommended that the trigger pulse width be set greater than 1ms to
ensure proper turn-on of the device.
IVFM Register (0x02)
Bit 7
RFU
Bit 6
UVLO
Circuitry
0=Disabled
(Default)
1=Enabled
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Bit 5
Bit 4
IVFM Levels
000=2.9 V (Default)
001=3.0 V
010=3.1 V
011=3.2 V
100=3.3 V
101=3.4 V
110=3.5 V
111=3.6 V
24
Bit 3
Bit 2
RFU
Bit 1
RFU
Bit 0
IVFM Enable
0=Disabled
(Default)
1=Enabled
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AW36518
Oct. 2018 V1.0
LED Flash Brightness Register (0x03)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
LED Flash Brightness Levels
IFLASH(mA)≈(Brightness Code*5.88mA)+2.94mA
00000000=2.94 mA
……………
01111111=748.52 mA
……………
11111111=1.5 A
(Default)
LED Torch Brightness Register (0x05)
Bit 7
Bit 6
Bit 5
LED Torch Brightness Levels
ITORCH(mA)≈(Brightness Code*1.51mA)+0.75mA
00000000=0.75 mA
……………
01111111=192 mA (Default)
……………
11111111=386 mA
Boost Configuration Register (0x07)
Bit 7
Software
Reset Bit
0=Not Reset
(Default)
1=Reset
RFU
Bit 5
RFU
RFU
LED Pin
Short Fault
Detect
0=Disabled
1=Enabled
(Default)
Boost Mode
0=Normal
(Default)
1=Pass Mode
Only
Boost
Frequency
Select
0=2 MHz
(Default)
1=4 MHz
Boost
Current Limit
0=1.9A
1=2.8A
(Default)
Timing Configuration Register (0x08)
Bit 7
RFU
Bit 6
Bit 6
Bit 5
Bit 4
Torch Current Ramp time
000=No Ramp
001=1 ms (Default)
010=32 ms
011=64 ms
100=128 ms
101=256 ms
110=512 ms
111=1024 ms
Bit 3
Bit 2
Bit 1
Bit 0
Bit 1
Bit 0
Flash Time-out Duration
0000=40 ms
0001=80 ms
0010=120 ms
0011=160 ms
0100=200 ms
0101=240 ms
0110=280 ms
0111=320 ms
1000=360 ms
1001=400 ms
1010=600 ms (Default)
1011=800 ms
1100=1000 ms
1101=1200 ms
1110=1400 ms
1111=1600 ms
Flags1 Register (0x0A)
Bit 7
TX Flag
Bit 6
VOUT Short
Fault
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Bit 5
LED Short
Fault
Bit 4
LED Short
Fault
25
Bit 3
Current Limit
Flag
Bit 2
Thermal
Shutdown
(TSD) Fault
UVLO Fault
Flash
Time-Out
Flag
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AW36518
Oct. 2018 V1.0
Flags2 Register (0x0B)
Bit 7
RFU
Bit 6
RFU
RFU
Bit 6
RFU
RFU
Bit 3
RFU
Bit 2
IVFM Trip
Flag
Bit 1
OVP Fault
Bit 0
RFU
Bit 5
RFU
Bit 4
Bit 3
Device ID
“01”
Bit 2
Bit 1
Bit 0
Silicon Revision Bits
“010”
Last Flash Register (0x0D)
Bit 7
RFU
RFU
Bit 4
Device ID Register (0x0C)
Bit 7
Bit 5
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
The value stored is always the last current value the IVFM detection block set ILED=IFLASH-TARGET*((code+1)/256)
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Application Information
The AW36518 can drive a flash LED at current up to 1.5A. The 2MHz/4MHz DC-DC boost regulator allows for
the use of small value discrete external components. Below are some peripheral selection guidelines.
Output Capacitor Selection
The AW36518 is designed to operate with a 10µF ceramic output capacitor. When the boost converter is
running, the output capacitor supplies the load current during the boost converter on-time. When the NMOS
switch turns off, the inductor energy is discharged through the internal PMOS switch, supplying power to the
load and restoring charge to the output capacitor. This causes a sag in the output voltage during the on-time
and a rise in the output voltage during the off-time. The output capacitor is therefore chosen to limit the output
ripple to an acceptable level depending on load current and input/output voltage differentials and also to
ensure the converter remains stable.
Larger capacitors such as a 22µF or capacitors in parallel can be used if lower output voltage ripple is desired.
To estimate the output voltage ripple considering the ripple due to capacitor discharge (ΔVQ) and the ripple
due to the capacitors ESR (ΔVESR) use the following equations:
For continuous conduction mode, the output voltage ripple due to the capacitor discharge is:
VQ
(VOUT VIN ) I LED
VOUT f COUT
The output voltage ripple due to the output capacitors ESR is found by:
V I
I
VESR RESR OUT LED L
VIN
2
I L
Where
VIN (VOUT VIN )
VOUT f L
In ceramic capacitors the ESR is very low so the assumption is that 80% of the output voltage ripple is due to
capacitor discharge and 20% from ESR. Table 1 lists different manufacturers for various output capacitors
and their case sizes suitable for use with the AW36518.
Input Capacitor Selection
Choosing the correct size and type of input capacitor helps minimize the voltage ripple caused by the
switching of the AW36518 boost converter and reduce noise on the boost converter's input pin that can feed
through and disrupt internal analog signals. In the typical application circuit a 10-µF ceramic input capacitor
works well. It is important to place the input capacitor as close as possible to the AW36518 input (IN) pin. This
reduces the series resistance and inductance that can inject noise into the device due to the input switching
currents. Table 1 lists various input capacitors recommended for use with the AW36518.
Table 1 Recommended Input/ Output Capacitors (X5R/X7R Dielectric)
MANUFACTURER
PART NUMBER
VALUE
CASE
VOLTAGE RATING
TDK
C1608JB0J106M
10μF
0603
6.3V
TDK
C2012JB1A106M
10μF
0805
10V
Murata
GRM188R60J106M
10μF
0603
6.3V
Murata
GRM21BR61A106KE19
10μF
0805
10V
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Inductor Selection
The AW36518 is designed to use a 0.47µH or 1µH inductor. When the device is boosting (VOUT > VIN) the
inductor is typically the largest area of efficiency loss in the circuit. Therefore, choosing an inductor with the
lowest possible series resistance is important. Additionally, the saturation rating of the inductor should be
greater than the maximum operating peak current of the AW36518. This prevents excess efficiency loss that
can occur with inductors that operate in saturation. For proper inductor operation and circuit performance,
ensure that the inductor saturation and the peak current limit setting of the AW36518 are greater than IPEAK in
the following calculation:
I PEAK
I LED VOUT
I L
VIN
I L
where
VIN VOUT VIN
2 f SW L VOUT
And f SW =2 or 4MHz.
Table 2 lists various inductors and their manufacturers that work well with the AW36518.
Table 2 Recommended Inductors
MANUFACTURER
L
PART NO.
SIZE
ISAT
RDC
TOKO
1μH
DFE201610P-1R0M
2.0 mm x 1.6 mm x 1.0 mm
3.7A
58mΩ
TOKO
0.47μH
DFE201610P-R470M
2.0 mm x 1.6 mm x 1.0 mm
4.1A
32mΩ
Sunlord
1μH
WPN252012H1R0MT
2.5mm × 2.0mm ×1.2mm
3.4A
48mΩ
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
PCB Layout Consideration
Layout Guidelines
The high switching frequency and large switching currents of the AW36518 make the choice of layout
important. The following steps should be used as a reference to ensure the device is stable and maintains
proper LED current regulation across its intended operating voltage and current range.
1. Place CIN on the top layer (same layer as the AW36518) and as close to the device as possible. The input
capacitor conducts the driver currents during the low-side MOSFET turn-on and turn-off and can detect
current spikes over 1 A in amplitude. Connecting the input capacitor through short, wide traces to both the
IN and GND pins reduces the inductive voltage spikes that occur during switching which can corrupt the
VIN line.
2. Place COUT on the top layer (same layer as the AW36518) and as close as possible to the OUT and GND
pin. The returns for both CIN and COUT should come together at one point, as close to the GND pin as
possible. Connecting COUT through short, wide traces reduce the series inductance on the OUT and GND
pins that can corrupt the VOUT and GND lines and cause excessive noise in the device and surrounding
circuitry.
3. Connect the inductor on the top layer close to the SW pin. There should be a low-impedance connection
from the inductor to SW due to the large DC inductor current, and at the same time the area occupied by
the SW node should be small so as to reduce the capacitive coupling of the high dV/dT present at SW
that can couple into nearby traces.
4. Avoid routing logic traces near the SW node so as to avoid any capacitive coupling from SW onto any
high-impedance logic lines such as TX, STROBE/TORCH, SDA, and SCL. A good approach is to insert
an inner layer GND plane underneath the SW node and between any nearby routed traces. This creates a
shield from the electric field generated at SW.
5. Terminate the Flash LED cathodes directly to the GND pin of the AW36518. If possible, route the LED
returns with a dedicated path so as to keep the high amplitude LED currents out of the GND plane. For
Flash LEDs that are routed relatively far away from the AW36518, a good approach is to sandwich the
forward and return current paths over the top of each other on two layers. This helps reduce the
inductance of the LED current paths.
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Package Description
Pin1 Corner
TOP VIEW
SIDE VIEW
0.40 TYP
D
C
SYMM
℄
B
A
1
2
SYMM
℄
3
BOTTOM VIEW
Unit: mm
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Land Pattern Data
0.40 TYP
A
0.40 TYP
B
SYMM
℄
C
D
2
1
3
SYMM
℄
0.05 MAX
All AROUND
0.05 MIN
All AROUND
SOLDER MASK
OPENING
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
METAL
NO N SOLDER MASK DEFINED
SOLDER MASK DEFINED
Unit: mm
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Tape and Reel Information
TAPE DIMENSIONS
REEL DIMENSIONS
P1
P0
P2
K0
W
B0
D1
A0
Cavity
A0：Dimension designed to accommodate the component width
B0：Dimension designed to accommodate the component length
K0：Dimension designed to accommodate the component thickness
W：Overall width of the carrier tape
P0：Pitch between successive cavity centers and sprocket hole
P1：Pitch between successive cavity centers
P2：Pitch between sprocket hole
D1：Reel Diameter
D0：Reel Width
D0
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE
Pin 1
Sprocket Holes
Q1
Q2
Q1
Q2
Q1
Q2
Q1
Q2
Q3
Q4
Q3
Q4
Q3
Q4
Q3
Q4
User Direction of Feed
Pocket Quadrants
DIMENSIONS AND PIN1 ORIENTATION
D1
(mm)
D0
(mm)
A0
(mm)
B0
(mm)
K0
(mm)
P0
(mm)
P1
(mm)
P2
(mm)
W
(mm)
Pin1
Quadrant
180
9.5
1.4
1.85
0.75
2
4
4
8
Q1
All dimensions are nominal
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
Revision History
Version
Date
Change Record
V1.0
Oct. 2018
Product Datasheet V1.0 Released
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Copyright © 2018 SHANGHAI AWINIC TECHNOLOGY CO., LTD
AW36518
Oct. 2018 V1.0
DISCLAIMER
Information in this document is believed to be accurate and reliable. However, Shanghai AWINIC Technology
Co., Ltd (AWINIC Technology) does not give any representations or warranties, expressed or implied, as to
the accuracy or completeness of such information and shall have no liability for the consequences of use of
such information.
AWINIC Technology reserves the right to make changes to information published in this document, including
without limitation specifications and product descriptions, at any time and without notice. Customers shall
obtain the latest relevant information before placing orders and shall verify that such information is current and
complete. This document supersedes and replaces all information supplied prior to the publication hereof.
AWINIC Technology products are not designed, authorized or warranted to be suitable for use in medical,
military, aircraft, space or life support equipment, nor in applications where failure or malfunction of an
AWINIC Technology product can reasonably be expected to result in personal injury, death or severe property
or environmental damage. AWINIC Technology accepts no liability for inclusion and/or use of AWINIC
Technology products in such equipment or applications and therefore such inclusion and/or use is at the
customer’s own risk.
Applications that are described herein for any of these products are for illustrative purposes only. AWINIC
Technology makes no representation or warranty that such applications will be suitable for the specified use
without further testing or modification.
All products are sold subject to the general terms and conditions of commercial sale supplied at the time of
order acknowledgement.
Nothing in this document may be interpreted or construed as an offer to sell products that is open for
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industrial or intellectual property rights.
Reproduction of AWINIC information in AWINIC data books or data sheets is permissible only if reproduction
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AWINIC is not responsible or liable for such altered documentation. Information of third parties may be subject
to additional restrictions.
Resale of AWINIC components or services with statements different from or beyond the parameters stated by
AWINIC for that component or service voids all express and any implied warranties for the associated
AWINIC component or service and is an unfair and deceptive business practice. AWINIC is not responsible or
liable for any such statements.
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