202075B.pdf

DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
General Description
Features
The AAT2893 family is a highly-integrated lighting management unit (LMU) optimized for single-cell lithium-ion/
polymer battery powered systems and is ideal for portable devices.
WLED Driver
The AAT2893 integrates a high voltage DC/DC boost converter and an internally programmed over-voltage protection circuit. It drives 10 LEDs (or more) in series1
controlled by a high precision, 128-step current sink,
programmable up to 28.6mA. The high frequency PWM
dimming implementation is compliant with Content
Adaptive Brightness Control (CABC) specification with a
PWM frequency up to 100kHz. The ambient light sensor
(ALS) management function features automatic sensor
calibration, enabling system designers to use low cost
photo diodes, and 50Hz/60Hz noise rejection for accurate
brightness adjustment without processor intervention.
The AAT2893 also contains four high-performance, lownoise and low dropout (LDO) linear regulators. Each
regulator starts up with a default 1.2V and is adjustable
by programming through the I2C interface. LDOA can
supply up to 300mA, while LDOB, C and D can source up
to 150mA to a system load.
All AAT2893 functions are programmed using an industry
standard bi-directional I2C interface.
The AAT2893 is available in a Pb-free, space saving
2.0mm x 2.5mm, 20-ball CSP package rated over a
-40°C to +85°C temperature range.
• 1.3MHz Switching Frequency
• Over-voltage Protection
▪ AAT2893-1 up to 42V
▪ AAT2893-2 up to 33V
• Automatic Soft Start
• Programmable Backlight Current
▪ 28.6mA Maximum Current
▪ 128 Levels (7-bit): 0 – 28.6mA
▪ Programmable Fade-in and Fade-out
• Advanced Dimming Features
▪ Ambient Light Sensor Management
▪ Direct Ambient Dimming Function
- 128 Programmable Levels
▪ CABC Compatible PWM Dimming
Four Linear Regulators
▪ LDOA up to 300mA
▪ LDOB, LDOC and LDOD up to 150mA
▪ 150mV Dropout
▪I2C Programmable Outputs: 1.2V to 3.3V
▪ Output Auto-Discharge for Fast Shutdown
• Input Voltage Range: 3.0V to 5.5V
• Built-In Over-temperature Protection
• Industry Standard I2C Programming Interface
• -40°C to 85°C Temperature Range
• 2.0mm x 2.5mm, 20 Ball, 0.4mm Pitch CSP Package
Applications
• Camera Enabled Mobile Devices
• Digital Still Cameras
• Multimedia Mobile Phones
Part Number
I2C Address2
Over-voltage Protection Level (V)
AAT2893-1
AAT2893-2
60h
60h
42
33
1. The actual number of series LEDs depends on OVP and VF of WLED.
2. Other I2C addresses available, contact factory.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
1
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Application Circuit
DS1
L1
VOUT Backlight
4.7μH
VBAT
3.6V
CIN
4.7μF
COUT
0.1μF
LX
IN
OUT
IN_LDO
CIN_LDO
2.2μF
Enable
EN
I2C Data Input
SDA
2
I C Clock Input
SCL
PWM Control Input
CCOMP
56nF
CFLTR
10nF
CSBIAS
2.2μF
AAT2893
ILED
PWM
LDOA
COMP
LDOB
VLDOB
150mA
FLTR
2
AMB _IN
AGND
CLDOA
4.7μF
2.2μF
SBIAS
LDOC
External Ambient
Light Sensor
(Photo Diode )
VLDOA
300mA
LDOD
PGND
CLDOD
2.2μF
VLDOD
150mA
VLDOC
150mA
CLDOC
2.2μF
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Pin Descriptions
Pin #
Symbol
A1
LDOD
A2
LDOC
A3
LDOB
A4
LDOA
B1
IN_LDO
B2
IN
B3
EN
B4
SBIAS
C1
C2
C3
AGND
DGND
SCL
C4
AMB_IN
D1
D2
D3
D4
E1
E2
PGND
PWM
SDA
FLTR
LX
OUT
E3
ILED
E4
COMP
Description
LDOD regulated voltage output pin. Bypass LDOD to AGND with a 2.2μF or larger capacitor as close to the
AAT2893 as possible.
LDOC regulated voltage output pin. Bypass LDOC to AGND with a 2.2μF or larger capacitor as close to the
AAT2893 as possible.
LDOB regulated voltage output pin. Bypass LDOB to AGND with a 2.2μF or greater capacitor as close to the
AAT2893 as possible.
LDOA regulated voltage output pin. Bypass LDOA to AGND with a 4.7μF or larger ceramic capacitor as close to
the AAT2893 as possible.
Input power supply pin for all four LDO voltage regulators. Bypass IN_LDO to PGND with a 2.2μF or larger ceramic capacitor located as close to the AAT2893 as possible.
Power input. Connect IN to the input source voltage. Bypass IN to PGND with a 4.7μF or larger ceramic capacitor
as close to the AAT2893 as possible.
Enable Pin. Drive high to enable, low to shutdown.
Ambient light sensor bias supply output. This pin provides a regulated bias supply to the attached ambient light
sensor.
Analog ground. Connect AGND to PGND at a single point as close to the AAT2893 as possible.
Digital ground. Connect AGND and DGND and PGND at a single point as close to the AAT2893 as possible.
I2C Serial Clock input pin
Ambient light sensor input connection pin. Connect the photo diode anode or ambient light sensor module output to this pin.
Power ground. Connect AGND to PGND at a single point as close to the AAT2893 as possible.
Content controlled backlight brightness PWM signal input pin. Pull high to disable the PWM dimming feature.
I2C Serial Data pin, this pin is bi-directional.
PWM input filter capacitor pin. Connect a 10nF ceramic capacitor between this pin and AGND.
Boost converter switching node. Connect a inductor between this node and IN.
Boost converter output, place an external schottky between this node and LX
Series LED string current sink. ILED controls the current through backlight LED constant current sink. Connect to
the cathode of the last LED in the LED string.
Compensation pin. Connect a capacitor via this pin to GND. Compensation components are mainly related to the
output capacitor value.
Pin Configurations
2.0mm × 2.5mm, 4 × 5 Ball Array CSP
(Top View)
1
2
3
4
A
LDOD
LDOC
LDOB
LDOA
B
IN_LDO
IN
EN
SBIAS
C
AGND
DGND
SCL
AMB_IN
D
PGND
PWM
SDA
FLTR
E
LX
OUT
ILED
COMP
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
3
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Absolute Maximum Ratings1
Symbol
Description
VIN, VIN_LDO
Input Voltage to AGND, PGND
VLX, VILED, VOUT
High Voltage to AGND, PGND
EN, SDA, SCL,
COMP, PWM, FLTR,
SBIAS, LDOA, LDOB,
LDOC, LDOD
VAMB-IN
Value
Units
-0.3 to 6
-0.3 to 50
-0.3 to 44
AAT2893-1
AAT2893-2
V
Pin Voltage to AGND, PGND
-0.3 to VIN+0.3
Ambient Light Sensor Maximum Input Voltage to AGND, PGND
VIN
Thermal Information2
Symbol
ΘJA
PD
TJ
TLEAD
Description
Thermal Resistance
Maximum Power Dissipation
Operating Junction Temperature Range
Maximum Soldering Temperature (at Leads, 10s)
3
Value
Units
79
1.26
-40 to 150
300
°C/W
W
°C
Recommended Operating Conditions
Symbol
Description
VIN
VOUT
L1
fPWM-F
TA
Input Supply Voltage
Boost Converter Output Voltage
Inductor Value
Filtered PWM Input Frequency
Ambient Operating Temperature
Value
Min
3.0
VIN+3V
4.7
0.1
-40
Typ
Max
10
5.5
VOVP_T
22
100
85
25
Units
V
µH
kHz
°C
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions
specified is not implied.
2. Mounted on a FR4 circuit board.
3. Derate 12.6mW/°C above 25°C ambient temperature.
4
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Electrical Characteristics1
VIN = 3.6V; CIN = 4.7μF; CCOMP = 56nF; COUT = CSBIAS = 2.2µF; L = 4.7μH; TA = -40°C to +85°C, unless otherwise noted.
Typical values are TA = 25°C.
Symbol
Description
Boost Converter Input Operating
VIN
Voltage Range
IN Operating Current Standby / No
IQIN
Load
IQIN(SW)
IN Operating Current (Switching)
IIN(SHDN)
IN Shutdown Current
Over-temperature Shutdown
TSD
Threshold
Over-Temperature Shutdown
TSD(HYS)
Hysteresis
DMIN
Minimum PWM dimming Duty Cycle
DC/DC Boost Section
RDS(ON)
Switch On-Resistance
η
Maximum Efficiency
fOSC
Switching Frequency
tss
Soft-start Time
DMAX
Maximum Duty Cycle
IL_LIMIT
Inductor Current Limit
OUT Over Voltage Protection
VOVP_T
Threshold
VOVPH
Over Voltage Protection Hysteresis
Conditions
Min
Typ
Max
Units
5.5
V
3.0
EN = VIN; ILED = OFF via I2C
400
µA
EN = VIN; No Load / ILED = ON
EN = 0; ILED = OFF via I2C
2.3
1.0
150
15
TA = 25°C
L1 = 10µH, IOUT = 28.6mA, VOUT = 36V
TA = 25°C
TA = 25°C
1.17
VOVP Rising
38
30.4
AAT2893-1
AAT2893-2
°C
8
%
650
82
1.3
4
mΩ
%
MHz
ms
%
mA
1.43
94
AAT2893-1
AAT2893-2
mA
µA
800
42
33
2.8
2.2
45
36
V
ILED Driver
IILED
ILED Current Accuracy
tFADE
ILED Automatic Fade In/Out Timer
Ambient Light Sensor Interface
Ambient Light Sensor Bias Voltage
VSBIAS
Output Tolerance
IOUT(SBIAS)[MAX]
SBIAS Maximum Output Current
Ambient Light Sensor Full Scale
VALS(FS)
Input Voltage
IIN(ALS)[MAX]
ALS ADC maximum input current
ROUT(SBIAS)[DCHG] SBIAS Auto-Discharge Resistance
VIN – VF = 1V, Set ILED = 19.8mA by I2C
VIN – VF = 1V, Set ILED = 2.03mA by I2C
VIN – VF = 1V
17.8
1.62
0.75
19.8
2.03
1
21.79
2.43
1.25
mA
mA
s
Set VSBIAS = 3.0V by I2C, ISBIAS = 200µA
Set VSBIAS = 2.6V by I2C, ISBIAS = 200µA
2.85
2.47
30
3.0
2.60
3.15
2.73
V
mA
1.6
V
1
1
µA
kΩ
1. The AAT2893 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls.
2. Current matching is defined as the deviation of any sink current from the average of all active channels.
3.VDO[A/B/C/D] is defined as VIN – LDO[A/B/C/D] when LDO[A/B/C/D] is 98% of nominal.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
5
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Electrical Characteristics (continued)1
VIN = 3.6V; CIN = 4.7μF; CCOMP = 56nF; COUT = CSBIAS = 2.2µF; L = 4.7μH; TA = -40°C to +85°C, unless otherwise noted.
Typical values are TA = 25°C.
Symbol
Description
Conditions
Min
Typ
Max
Units
5.5
V
2
3.0
%
Linear Regulators
VIN_LDO
ΔVOUT[A/B/C,D]/
VOUT[A/B/C,D]
IOUT[A](MAX)
VOUT[A](DO)
IOUT[B/C,D](MAX)
VOUT[B/C,D](DO)
∆VOUT/
(VOUT · ∆VIN)
LDOA, LDOB, LDOC, LDOD Output
Voltage Tolerance
LDOA Maximum Load Current
LDOA Dropout Voltage3
LDOB, LDOC, LDOD Maximum Load
Current
LDOB, LDOC, LDOD Dropout Voltage3
IOUT = 1mA to 150mA; TA = 25°C
IOUT = 1mA to 150mA; TA = -40°C to +85°C
VOUT[B/C/D] ≥ 3.0V; IOUT = 150mA
150
mV
Line Regulation
VIN = (VOUT[A/B/C/D] + 1V) to 5V
0.09
%/V
50
dB
1
kΩ
LDOA, LDOB, LDOC, LDOD Power
Supply Rejection Ratio
LDOA, LDOB, LDOC, LDOD AutoROUT_(DCHG)
Discharge Resistance
Input Threshold Levels - EN, PWM
VTH(L)
Input Low Threshold
VTH(H)
Input High Threshold
I2C Logic and Control Interface
VIL
SDA, SCL, EN Input Low Threshold
VIH
SDA, SCL, EN Input High Threshold
VOL
SDA Output Low Voltage
IIN
SDA, SCL, EN Input Leakage Current
fSCL
SCL Clock Frequency
tLOW
SCL Clock Low Period
tHIGH
SCL Clock High Period
tHD_STA
Hold Time START Condition
tSU_DAT
SDA Data Setup Time
tHD_DAT
SDA Data HOLD Time
tSU_STO
Setup Time for STOP Condition
Bus Free Time Between STOP and
tBUF
START Conditions
PSRR[A/B/C,D]
VOUT +
VDO
LDO Regulator Input Supply
-2
-3.0
300
VOUT[A] ≥ 3.0V; IOUT = 300mA
mA
mV
200
150
IOUT[A/B/C/D] = 10mA, 1kHz
mA
0.4
1.4
3.0V ≤ VIN ≤ 5.5V
3.0V ≤ VIN ≤ 5.5V
IPULLUP = 3mA
VSDA = VSCL
V
0.4
1.4
-1
0
1.3
0.6
0.6
100
0
0.6
V
0.4
1
400
µA
kHz
µs
ns
0.9
µs
1.3
1. The AAT2893 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls.
6
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
I2C Interface Timing Details
SDA
t SU_DAT
t LOW
t HD_STA
t BUF
SCL
t HD_STA
t HD_DAT
t HIGH
t SU_STA
t SU_STO
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
7
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
IQ vs Supply Voltage
IQ vs Supply Voltage
(Enable LDO, Disable LED via I2C, ILDO = 0)
640
640
580
580
520
520
460
460
IQ (µA)
IQ (µA)
(LED = OFF , Disable LDO via I2C)
400
340
400
340
280
25°C
280
220
-40°C
220
-40°C
160
85°C
160
85°C
100
3
3.3
3.6
3.9
4.2
4.5
4.8
5.1
100
5.4
Supply Voltage (V)
LED Current (mA)
LED Current (mA)
30
28
27
26
10
35
60
3.9
4.2
4.5
4.8
5.1
29
28
27
26
-15
10
35
60
85
Temperature (°C)
Shutdown Current vs Temperature
LED Current vs Register (Addr. 00h) Code
(4.7µH , 10 WLEDs)
(VIN = 3.6V , EN = GND)
30
0.8
25
LED Current (mA)
1
0.6
0.4
0.2
0
20
15
VIN = 3.0V
VIN = 3.6V
10
VIN = 4.2V
VIN = 5.0V
5
VIN = 5.5V
-0.2
-40
-15
10
35
Temperature (°C)
8
60
5.4
(AAT2893-1, VIN = 3.6V, ILED = 28.6mA, 10 WLEDs)
25
-40
85
Temperature (°C)
ISHUTDOWN (µA)
3.6
LED Current vs Temperature
29
-15
3.3
Supply Voltage (V)
(AAT2893-2, VIN = 3.6V, ILED = 28.6mA, 8 WLEDs)
25
-40
3
LED Current vs Temperature
30
25°C
0
85
0
10
20
30
40
50
60
70
80
90
100 110 120
Register (Addr. 00h) Code
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
PWM Duty vs LED Current
PWM Duty vs LED Current
(AAT2893-2 10 WLEDs)
30
30
25
25
LED Current (mA)
LED Current (mA)
(AAT2893-1 10 WLEDs)
20
15
VIN = 3.0V
VIN = 3.6V
10
VIN = 4.2V
VIN = 5.0V
5
0
20
15
VIN = 3.0
VIN = 3.6
10
VIN = 4.2
VIN = 5.0
5
VIN = 5.5V
VIN = 5.5
0
0
10
20
30
40
50
60
70
80
90
100
PWM Duty (%)
0
50
60
70
80
90
100
(AAT2893-2, ILED = 28.6mA , 8 WLEDs)
30
LED Current (mA)
LED Current (mA)
40
LED Current vs Supply Voltage
30
29
28
25C
27
-40C
85C
3
3.5
4
4.5
5
29.2
28.4
27.6
25°C
26.8
26
5.5
Supply Voltage (V)
-40°C
85°C
3
80
75
75
Efficiency (%)
80
70
65
55
VIN = 3.6V
50
VIN = 4.2V
VIN = 5.0V
5
10
15
20
LED Current (mA)
25
70
65
60
VIN = 3.0V
55
VIN = 3.6V
50
VIN = 4.2V
VIN = 5.0V
45
VIN = 5.5V
0
5.5
(AAT2893-2, 8 WLEDs)
85
VIN = 3.0V
5
4.5
Efficiency vs LED Current
85
60
4
Supply Voltage (V)
(AAT2893-1, 10 WLEDs)
45
3.5
Efficiency vs LED Current
Efficiency (%)
30
PWM Duty (%)
(AAT2893-1, ILED = 28.6mA , 10 WLEDs)
40
20
LED Current vs Supply Voltage
26
10
40
30
VIN = 5.5V
0
5
10
15
20
25
30
LED Current (mA)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
9
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
Efficiency vs Register Dimming Code (Addr. 00h)
(4.7µH , 10LEDs)
90
2.7
Under-Voltage Lockout Thresholds vs
Temperature
VIN Rising
UVLO Threshold (V)
80
Efficiency (%)
70
60
50
VIN = 3.0V
40
VIN = 3.6V
30
VIN = 4.2V
20
VIN = 5.0V
10
0
VIN = 5.5V
0
5
10
15
20
25
30
Register Dimming Code (Addr.00h)
2.3
2.1
1.9
1.7
-40
Frequency (MHz)
Frequency (MHz)
1.40
1.30
1.25
10
35
60
35
60
(AAT2893-1, VIN = 3.6V, ILED = 28.6mA, 10 WLEDs)
1.35
1.30
1.25
1.20
-40
85
Temperature (°C)
-15
10
35
60
Enable Threshold vs Temperature
(VIN = 3.6V)
1.4
1.4
EN_High
Enable Threshold (V)
Enable Threshold (V)
EN_High
EN_Low
1.2
1
0.8
0.6
3
3.3
3.6
3.9
4.2
4.5
Voltage (V)
10
85
Temperature (°C)
Enable Threshold vs Supply Voltage
0.4
2.7
85
Frequency vs Temperature
1.35
-15
10
Temperature (°C)
(AAT2893-2, VIN = 3.6V, ILED = 28.6mA, 8 WLEDs)
1.20
-40
-15
Frequency vs Temperature
1.40
VIN Falling
2.5
4.8
5.1
5.4
1
0.8
0.6
0.4
-40
5.7
EN_Low
1.2
-15
10
35
60
Temperature (°C)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
85
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
OVP vs Temperature
Boost Switch-On Resistance vs Temperature
(VIN = 3.6V, LED Open)
Switch-On Resistance (mΩ)
OVP Protection (V)
45
44
43
42
41
40
39
38
-40
-15
10
35
60
85
Temperature (°C)
(VIN = 3.6V )
900
800
700
600
500
400
300
-40
-15
10
35
60
85
Temperature (°C)
ALS Read Data vs IAMB_IN in Low Gain Mode
Addr08h (AMLRB) Read Data
(Gain Resistor = 4kΩ, VIN = 3.6V)
120
110
100
90
80
70
60
50
40
30
20
10
0
Addr07 = 01
Addr07 = 02
Addr07 = 03
Addr07 = 04
Addr07 = 05
Addr07 = 06
Addr07 = 07
Addr07 = 08
Addr07 = 09
Addr07 = 10
Addr07 = 11
Addr07 = 12
Addr07 = 13
Addr07 = 14
Addr07 = 15
Addr07 = 00
0
100
200
300
400
500
600
700
800
900
1000
IAMB_IN (µA)
LDOB/C/D Dropout Voltage vs Load
LDOB/C/D Dropout Voltage (mV)
LDOA Dropout Voltage (mV)
LDOA Dropout Voltage vs Load
200
160
120
80
VOUT = 2.5V
40
VOUT = 3.0V
VOUT = 3.3V
0
0
30
60
90
120
150
Load Current (mA)
180
210
240
200
160
120
80
VOUT = 2.5V
40
0
VOUT = 3.0V
VOUT = 3.3V
0
30
60
90
120
150
Load Current (mA)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
11
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
VLDOA Accuracy vs Temperature
VLDOB/C/D Accuracy vs Temperature
2.0
VLDOB/C/D Accuracy (%)
VLDOA Accuracy (%)
2.0
1.2
0.4
-0.4
-1.2
VOUT = 1.2V
1.2
0.4
-0.4
VOUT = 1.2V
-1.2
VOUT = 3.3V
VOUT = 3.3V
-2.0
-40
-15
10
35
60
-2.0
85
Temperature (°C)
-40
85
0.800
Load Regulation (%)
Load Regulation (%)
60
(VIN = 3.6V , VLDOA = 3.3V)
0.800
0.400
0.000
-0.400
0.400
0.000
-0.400
1
10
100
-0.800
1
1000
Load Current (mA)
1000
(VIN = 3.6V , VLDOB/C/D = 3.3V)
0.800
0.400
0.000
-0.400
-0.800
1
100
LDOB/C/D Output Voltage Load Regulation
(VIN = 3.6V , VLDOB/C/D = 1.2V)
Load Regulation (%)
0.800
10
Load Current (mA)
LDOB/C/D Output Voltage Load Regulation
Load Regulation (%)
35
LDOA Output Voltage Load Regulation
(VIN = 3.6V , VLDOA = 1.2V)
0.400
0.000
-0.400
10
100
Load Current (mA)
12
10
Temperature (°C)
LDOA Output Voltage Load Regulation
-0.800
-15
-0.800
1
1000
10
100
Load Current (mA)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
1000
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
Switching Operation
Switching Operation
(AAT2893-1, VIN = 3.6V, ILED = 19.8mA, 10 WLEDs)
(AAT2893-2, VIN = 3.6V, ILED = 19.8mA, 8 WLEDs)
VLX
VLX
0V
20V/div
20V/div
0V
VOUT(AC)
VOUT(AC)
100mV/div
50mV/div
IL
IL
500mA/div
500mA/div
0A
0A
I LED(AC)
I LED (AC)
2mA/div
2mA/div
Time (500ns/div)
Time (500ns/div)
OVP
Boost Start Up
(AAT2893-1, VIN = 3.6V, ILED = 28.6mA, 10WLEDs)
(VIN = 3.6V, Open LED)
VSDA
5V
VOUT
3V
4V/div
VLX
20V/div
3.6V
VOUT(AC)
20V/div
42V
5V/div
VLX
VIN(AC)
ILED
3.6V
20V/div
50mV/div
0mA
20mA/div
Time (10ms/div)
Time (10ms/div)
PWM Dimming Switching
PWM Dimming Switching
(VIN = 3.6V, Duty Cycle = 30%, ILED = 19.8mA)
(VIN = 3.6V, Duty Cycle = 80%, ILED = 19.8mA)
PWM
PWM
2V/div
2V/div
0V
VOUT(AC)
VOUT(AC)
VLX
VLX
ILED (AC)
1mA/div
ILED(AC)
1mA/div
0V
50mV/div
50mV/div
20V/div
20V/div
Time (50µs/div)
Time (50µs/div)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
13
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
Fade Out Characteristics
Fade In Characteristics
(AAT2893-1 VIN = 3.6V, ILED = 18.9mA, 10 WLEDs,
Fade Time = 1s, Fade Floor Current = 0.45mA)
VSDA
2V/div
VOUT
(AAT2893-1 VIN = 3.6V, ILED = 18.9mA, 10WLEDs,
Fade Time = 1s, Fade Floor Current = 0.45mA)
VSDA
5V
2V/div
26V
ILED
5V/div
10mA/div
Time (200ms/div)
Time (200ms/div)
LDO StartUp
LDO Output Voltage Change
(VIN = 3.6V, ILDO = 20mA, VLDO convert from 1.2V to 3.3V via I2C)
(VIN = 3.6V, VLDO = 2.5V, ILDO = 20mA)
0V
VSDA
VOUT
0V
1V/div
1V/div
Time (50µs/div)
Time (50µs/div)
LDOA Line Transient
LDOB/C/D Line Transient
(VIN = 3.6V ~ 5.5V, VLDOB/C/D = 2.5V, ILDOB/C/D = 20mA)
VIN
3.6V
VLDOA
VLDOB/C/D
2.5V
50mV/div
Time (100µs/div)
14
3.6V
1V/div
1V/div
50mV/div
1.2V
(VIN = 3.6V ~ 5.5V, VLDOA = 2.5V, ILDOA = 20mA)
VIN
0V
2V/div
2V/div
VOUT
19.8mA
ILED
0.45mA
10mA/div
VSDA
31.3V
VOUT
5V/div
5V
2.5V
Time (100µs/div)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Typical Characteristics
LDOA Load Transient
LDOB/C/D Load Transient
(VIN = 3.6V, ILDOB/C/D = 1mA~150mA, VLDOB/C/D = 2.5V)
(VIN = 3.6V, ILDOA= 1mA~300mA, VLDOA = 2.5V)
2.5V
VLDOB/C/D
VLDOA
50mV/div
50mV/div
ILDOA
100mA/div
2.5V
ILDOB/C/D
0mA
100mA/div
Time (100µs/div)
0mA
Time (100µs/div)
Cross Talk between LDOA and LDOB/C/D
(VIN = 3.6V, ILDOB/C/D = 1mA~150mA, VLDOA = VLDOB/C/D = 2.5V)
ILDOB/C/D
(100mA/div)
0mA
VLDOB/C/D
2.5V
VLDOA
2.5V
50mV/div
10mV/div
Time (100µs/div)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
15
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Functional Block Diagram
PGND
AMB _IN
OUT
DC/DC Boost
Converter Control
IN
SBIAS
LX
OVP
LDO
Regulator
Oscillator
Programmable
Amplifier
+
ADC
Backlight
Current
Control
EN
PWM
FLTR
COMP
Control
Logic
REF
SDA
SCL
I2C
Interface
LDOA
300mA
LDOA
LDOB
150mA
LDOB
LDOC
150mA
LDOC
LDOD
150mA
LDOD
Over Temperature
Monitor
IN_LDO
AGND
Functional Description
The AAT2893 integrates a high voltage DC/DC boost
converter and an internally programmed over-voltage
protection circuit. It drives up to 10 backlight LEDs in
series from a 3.0V to 5.5V input voltage source. To
reduce overall power consumption, the AAT2893 supports CABC by providing high frequency filtered PWM for
content based dimming and automatic ambient light
sensing for varying lighting conditions. The ambient light
control (ALC) includes a regulated bias supply to power
an ALS or a photo diode. The integrated ADC polls the
16
ILED
PGND
ambient light conditions and is readable through the I2C
interface. The ambient light control (ALC) can also be
configured to automatically adjust backlight brightness
for changing ambient lighting conditions.
LED Driver
The AAT2893 is capable of driving up to 10 backlight
LEDs in series with 128 programmable constant current
levels up to 28.6mA. The inductive DC/DC boost converter operates at a high, 1.3MHz switching frequency
allowing the use of small external 1.0μF-4.7μF ceramic
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
capacitors and requiring a 4.7µH-22µH inductor. The
output of the DC/DC boost converter is controlled by the
voltage across the LED current sink when programmed
for a desired LED forward current. An over-voltage protection feedback is provided to prevent damage to the
LED string or system when an over-voltage event occurs
at the output of the boost converter.
LED Current Control
The backlight LED string constant current level is controlled through the I2C interface. The backlight LED current can be set between 0mA and 28.6mA in steps of
approximately 0.23mA. All backlight LED functions
including fading, ambient light control and constant current levels are programmed through the I2C interface.
Ambient Light Sensing
The AAT2893 ALC circuit provides an interface and control for external ambient light sensor module or photo
diode. The system incorporates a programmable sensor
voltage bias supply (SBIAS) which may be configured to
output 3.0V, 2.8V, 2.7V or 2.6V and may source up to
30mA. The ALS input has a programmable gain amplifier
and ADC. The current ambient light level data can be
read through the I2C interface for other system functions. When the ALC is enabled to directly adjust the
backlight, the 16 internal registers with pre-configured
backlight dimming levels are used to profile 16 different
ambient lighting conditions. To save power and improve
system efficiency, the ALC circuit features manual polling
and automatic polling with programmable polling times.
Under polling control, the SBIAS regulator, ambient light
sensor and ADC circuit are disabled and only enabled for
a short period to sample and store the present ambient
light value in the ALS digital output read register. The
ADC continuously filters out the 50Hz and 60Hz flicker
noise from indoor lighting, eliminating the need for a
large capacitor at the output pin of the ambient light
sensor.
interface. Additionally, the I2C interface allows the LDO
regulators to be enabled independently for any combination of output voltages. The LDO regulators require a
small 2.2μF (LDOB/C/D) and a 4.7μF (LDOA) ceramic
output capacitor for maximized performance and stability. If improved load transient response is required,
larger value capacitors can be used without stability
degradation.
Serial Programmed Registers
The AAT2893 has 28 registers listed in Table 1:
• Four for backlight enable, control and configuration of
fade in/out function
• Twenty-one for ambient light sensor control and configuration and
• Three for LDOs control and configuration.
Backlight Current Programming
The backlight string current is disabled by default. The
backlight current can be easily configured by using ILED
(00h) registers. LED string needs to be enabled by setting BL_EN=1 from BL_ENBLS (01h) register. The current default setting is 19.8mA.
Fade In/Fade Out Programming
The fade in/out function allows LEDs to fade between
two programmed current levels in a smooth, logarithmic
progression. By default, fade in/out is enabled (bits
FADE_EN and FADE_INIT have a default value of 1). The
fade in/out function can be disabled by writing FADE_EN
=0 in FADE (03h) register. The fade function can be
interrupted by writing the FADE_EN bit to 0 when a fade
event is in progress. When this happens, the current will
abruptly change to the ceiling value programmed in
BL<7:0> bits in ILED register. The duration of the fade
in/out sequences can be programmed by setting
FTIME<1:0> in FADE register. The default fade in/out
timing is 1s.
LDO Regulators
Fade In Function
The AAT2893 includes four low dropout (LDO) linear
regulators. These regulators are programmable through
the I2C interface. LDOA is designed to provide load current up to 300mA, and LDOB, C and D are intended for
loads up to 150mA respectively. The output voltage of
each LDO can be set to one of 16 levels between 1.2V
and 3.3V. The LDO regulators turn on/off and regulate
output voltage level by programming through the I2C
At initial start up, the LED string turns on with a default
value of 19.8mA per channel unless fade in has been
specifically programmed. The lower current (floor) is
programmed using FLR[3:0] bits in FADE_FLR register.
The default is 0.45mA per channel. The higher current
(ceiling) is programmed using bits BL [6:0] in ILED
(00h) register. Fade in sequence is initiated when FADE_
INIT is changed from 0 to 1 in FADE (03h) register.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
17
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Fade Out Function
The fade out sequence is initiated when FADE_INIT is
changed from 1 to 0 in FADE (03h) register. The floor
current will persist until LED string is disabled by writing
BL_EN=1 to BL_ENBLS (01h) register.
I2C Serial Interface Protocol
The AAT2893 uses an I2C serial interface to set backlight
LED current, LDO on/off and output voltage, as well as
other housekeeping functions. The AAT2893 acts only as
a slave device. The I2C protocol uses two open-drain
inputs: SDA (serial data line) and SCL (serial clock line).
Both inputs require an external pull up resistor, typically
start
msb
Chip Address
lsb
w
ack
msb
to the input voltage. The I2C protocol is bidirectional.
The timing diagram in Figure 1 shows the typical I2C
interface protocol.
Devices on the I2C bus can either be a master or a slave.
Both master and slave devices can send and receive
data over the bus, the difference being that the master
device controls all communication on the bus. The I2C
communications begin by the master making a START
condition. Next the master transmits the 7-bit device
address and a Read/Write bit. Each slave device on the
bus has a unique address. The AAT2893's 7-bit
device address is 0x60.
Register Address
lsb
ack
msb
Register Data
lsb
ack
stop
SCL
SDA
start
AAT2893 Device Address
Id = 60h
w
ack
Addr = 0 0 h
ack
Address = 00h Data = 06h
ack
First Byte Writes as 0xC0
Figure 1: Typical I2C Timing Diagram.
18
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected]skyworksinc.com • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
stop
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
START and STOP Conditions
the SCL line low. A START condition acts as a signal to
devices on the bus that the device producing the START
condition is active and will be communicating on the bus.
START and STOP conditions are always generated by the
master. Prior to initiating a START, both the SDA and SCL
pin are inactive and are pulled high through external pullup resistors. As shown in Figure 2, a START condition
occurs when the master pulls the SDA line low and, after
the start condition hold time (tHT_STA), the master strobes
A STOP condition, as shown in Figure 2, occurs when SCL
changes from low to high followed after the STOP condition setup time (tSU_STO), by an SDA low-to-high transition. The master does not issue an ACK but releases SCL
and SDA.
STOP
START
SDA
SDA
SCL
SCL
tSU_STO
tHD_STA
Figure 2: I2C STOP and START Conditions;
START: A High “1” to Low “0” Transition on the SDA Line While SCL is High “1”
STOP: A Low “0” to High “1” Transition on the SDA Line While SCL is High “1”.
Transferring Data
device transmits an ACK signal to indicate that it has
received the transmission. The ACK signal is generated
by the target after the master releases the SDA data line
by driving SDA low.
Addresses and data are sent with the most significant bit
first transmitted and the least significant bit transmitted
last. After each address or data transmission, the target
SCL
1
2
3
4
5
6
7
MSB
SDA
A6
8
9
LSB
A5
A4
A3
A2
A1
A0
R/W
ACK
Device Address
Figure 3: I2C Address Bit Map;
7-bit Slave Address (A6-A0), 1-bit Read/Write (R/W), 1-bit Acknowledge (ACK).
SCL
1
2
3
4
5
6
7
MSB
SDA
D7
8
9
LSB
D6
D5
D4
D3
D2
D1
D0
ACK
Register Address /
Data
Figure 4: I2C Register Address and Data Bit Map;
8-bit Data (D7-D0), 1-bit Acknowledge (ACK).
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
19
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Writing to Slave Device
When the Read/Write bit is set to 0 and the address
transmitted by the master matches the slave device’s
address, the slave device transmits an Acknowledge
(ACK) signal to indicate that it is ready to receive data.
Next, the master transmits the 8-bit register address,
start
msb
Chip Address
lsb
w
ack
msb
and the slave device transmits an ACK to indicate that it
received the register address. After that, the master
transmits the 8-bit data word, and again the slave device
transmits an ACK indicating that it received the data.
This process continues until the master finishes writing
to the slave device at which time the master generates
a STOP condition.
Register Address
lsb
ack
msb
Register Data
lsb
ack
stop
SCL
SDA
start
AAT2893 Device Address
Id = 60h
w
ack
Addr = 0 0 h
ack
Address = 00h Data = 06h
ack
stop
First Byte Writes as 0xC0
Figure 5: AAT2893 I2C Write Timing Diagram.
Reading from Slave Device
When the Read/Write bit is set to 1 and the address
transmitted by the master matches the slave device’s
address, the slave device transmits an Acknowledge
(ACK) signal to indicate that it is ready to receive data.
start
msb
Chip Address
lsb
AAT2893 Device Address
Id = 60h
w
ack
r
ack
Next, the slave device transmits the 8-bit data word,
and the master reads the data byte and transmits an
Acknowledge ACK to indicate that it received the byte,
and generates a STOP condition.
msb
Register Data
lsb
stop
ack
SCL
SDA
start
Data = 0 8 h
ack
stop
First Byte Writes as 0xC1
Figure 6: AAT2893 I2C Read Timing Diagram.
20
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Serial Programmed Registers
The AAT2893's I2C programming registers are listed in Table 1.
Register
Hex
Code
Function
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
Figures
00h
Backlight LED
Current
0
BL[6]
BL[5]
BL[4]
BL[3]
BL[2]
BL[1]
BL[0]
Figure.7
01h
BL & CABC
Enables
0
0
0
0
0
0
BL_EN
CABC_EN
Figure.8
02h
Fade Floor
0
0
0
0
FLR[3]
FLR[2]
FLR[1]
FLR[0]
Figure.9
FADE
03h
Fade Control
FTIME[1]
FTIME[0]
FADE_EN
INIT_FADE
Figure.10
ALC_
FADE
04h
ALC Fade Time
ALCFU[1]
ALCFU[0]
ALCFD[1]
ALCFD[0]
Figure.11
ALS_
CFG0
05h
ALS Functions
PMODE
RSET[2]
RSET[1]
RSET[0]
GAIN[1]
GAIN[0]
GM_SEL
ALS_EN
Figure.12
ALS_
CFG1
06h
SBIAS ON/OFF
OFF_TM
OS_
ADJ[3]
OS_
ADJ[2]
OS_
ADJ[1]
OS_ADJ[0]
SB[1]
SB[0]
SB_EN
Figure.13
ALS_
CFG2
07h
ALS input
gain/offset
SNSR
ALSOUT
PTIME[1]
PTIME[0]
G_ADJ[3]
G_ADJ[2]
G_ADJ[1]
G_ADJ[0]
Figure.14
AMLRB
08h
Ambient Level
(Read)
AMB[7]
AMB[6]
AMB[5]
AMB[4]
AMB[3]
AMB[2]
AMB[1]
AMB[0]
Figure.15
ALS_BL0
09h
ALS Data
ALS0[6]
ALS0[5]
ALS0[4]
ALS0[3]
ALS0[2]
ALS0[1]
ALS0[0]
ALS_BL1
0Ah
ALS Data
ALS1[6]
ALS1[5]
ALS1[4]
ALS1[3]
ALS1[2]
ALS1[1]
ALS1[0]
ALS_BL2
0Bh
ALS Data
ALS2[6]
ALS2[5]
ALS2[4]
ALS2[3]
ALS2[2]
ALS2[1]
ALS2[0]
ALS_BL3
0Ch
ALS Data
ALS3[6]
ALS3[5]
ALS3[4]
ALS3[3]
ALS3[2]
ALS3[1]
ALS3[0]
ALS_BL4
0Dh
ALS Data
ALS4[6]
ALS4[5]
ALS4[4]
ALS4[3]
ALS4[2]
ALS4[1]
ALS4[0]
ALS_BL5
0Eh
ALS Data
ALS5[6]
ALS5[5]
ALS5[4]
ALS5[3]
ALS5[2]
ALS5[1]
ALS5[0]
ALS_BL6
0Fh
ALS Data
ALS6[6]
ALS6[5]
ALS6[4]
ALS6[3]
ALS6[2]
ALS6[1]
ALS6[0]
ALS_BL7
10h
ALS Data
ALS7[6]
ALS7[5]
ALS7[4]
ALS7[3]
ALS7[2]
ALS7[1]
ALS7[0]
ALS_BL8
11h
ALS Data
ALS8[6]
ALS8[5]
ALS8[4]
ALS8[3]
ALS8[2]
ALS8[1]
ALS8[0]
ALS_BL9
12h
ALS Data
ALS9[6]
ALS9[5]
ALS9[4]
ALS9[3]
ALS9[2]
ALS9[1]
ALS9[0]
ALS_BLA
13h
ALS Data
ALSA[6]
ALSA[5]
ALSA[4]
ALSA[3]
ALSA[2]
ALSA[1]
ALSA[0]
ALS_BLB
14h
ALS Data
ALSB[6]
ALSB[5]
ALSB[4]
ALSB[3]
ALSB[2]
ALSB[1]
ALSB[0]
ALS_BLC
15h
ALS Data
ALSC[6]
ALSC[5]
ALSC[4]
ALSC[3]
ALSC[2]
ALSC[1]
ALSC[0]
ALS_
BLD
16h
ALS Data
ALSD[6]
ALSD[5]
ALSD[4]
ALSD[3]
ALSD[2]
ALSD[1]
ALSD[0]
ALS_BLE
17h
ALS Data
ALSE[6]
ALSE[5]
ALSE[4]
ALSE[3]
ALSE[2]
ALSE[1]
ALSE[0]
ALS_BLF
18h
ALS Data
ALSF[6]
ALSF[5]
ALSF[4]
ALSF[3]
ALSF[2]
ALSF[1]
ALSF[0]
LDO_AB
19h
LDO Select
LDOA[3]
LDOA[2]
LDOA[1]
LDOA[0]
LDOB[3]
LDOB[2]
LDOB[1]
LDOB[0]
Figure.17
LDO_CD
1Ah
LDO Select
LDOC[3]
LDOC[2]
LDOC[1]
LDOC[0]
LDOD[3]
LDOD[2]
LDOD[1]
LDOD[0]
Figure.18
LDO_EN
1Bh
LDO Enable
0
0
0
0
LDO_END
LDO_ENC
LDO_ENB
LDO_ENA
Figure.19
Name
ILED
BL_ENBLS
FADE_
FLR
Figure.16
Table 1: AAT2893 Register Map. (“0” must be written 0; "blank" = Unassigned).
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
21
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
ILED: Backlight LED Current Control Register (Address 00h, Default 58h)
U-0
W-1
W-0
W-1
W-1
W-0
W-0
W-0
--
BL[6]
BL[5]
BL[4]
BL[3]
BL[2]
BL[1]
BL[0]
Bit 7
Bit 0
Bit 7
Unassigned
Bit 6 – Bit 0
BL<6:0>: Backlight LED Current Magnitude
0000000
0000001
0000010
0000011
0000100
0000101
0000110
0000111
0001000
0001001
0001010
0001011
0001100
0001101
0001110
0001111
0010000
0010001
0010010
0010011
0010100
0010101
0010110
0010111
0011000
0011001
0011010
0011011
0011100
0011101
0011110
0011111
0100000
0100001
0100010
0100011
0100100
0100101
0100110
0100111
0101000
0101001
0101010
0101011
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
0.00
0.23
0.45
0.68
0.90
1.13
1.35
1.58
1.80
2.03
2.25
2.48
2.70
2.93
3.15
3.38
3.60
3.83
4.05
4.28
4.50
4.73
4.95
5.18
5.40
5.63
5.85
6.08
6.30
6.53
6.75
6.98
7.20
7.43
7.65
7.87
8.10
8.32
8.55
8.77
9.00
9.22
9.45
9.67
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
0101100
0101101
0101110
0101111
0110000
0110001
0110010
0110011
0110100
0110101
0110110
0110111
0111000
0111001
0111010
0111011
0111100
0111101
0111110
0111111
1000000
1000001
1000010
1000011
1000100
1000101
1000110
1000111
1001000
1001001
1001010
1001011
1001100
1001101
1001110
1001111
1010000
1010001
1010010
1010011
1010100
1010101
1010110
1010111
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
9.90 mA
10.13 mA
10.35 mA
10.58 mA
10.80 mA
11.03 mA
11.25 mA
11.48 mA
11.70 mA
11.93 mA
12.15 mA
12.38 mA
12.60 mA
12.83 mA
13.05 mA
13.28 mA
13.50 mA
13.73 mA
13.95 mA
14.18 mA
14.40 mA
14.63 mA
14.85 mA
15.08 mA
15.30 mA
15.53 mA
15.75 mA
15.98 mA
16.20 mA
16.43 mA
16.65 mA
16.88 mA
17.10 mA
17.33 mA
17.55 mA
17.78 mA
18.00 mA
18.23 mA
18.45 mA
18.68 mA
18.90 mA
19.13 mA
19.35 mA
19.58 mA
1011000
1011001
1011010
1011011
1011100
1011101
1011110
1011111
1100000
1100001
1100010
1100011
1100100
1100101
1100110
1100111
1101000
1101001
1101010
1101011
1101100
1101101
1101110
1101111
1110000
1110001
1110010
1110011
1110100
1110101
1110110
1110111
1111000
1111001
1111010
1111011
1111100
1111101
1111110
1111111
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
19.80
20.03
20.25
20.48
20.70
20.93
21.15
21.38
21.60
21.83
22.05
22.28
22.50
22.73
22.95
23.18
23.40
23.63
23.85
24.08
24.30
24.53
24.75
24.98
25.20
25.43
25.65
25.88
26.10
26.33
26.55
26.78
27.00
27.23
27.45
27.68
27.90
28.13
28.35
28.58
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
mA
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Channel number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 7: Backlight Current Control Register.
22
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
BL_ENBLS: Backlight & CABC Enable Register (Address 01h Default 00h)
U-0
U-0
U-0
U-0
U-0
U-0
--
--
--
--
--
--
W-0
W-0
BL_EN CABC_EN
Bit 7
Bit 0
Bit 7 – Bit 2
Unassigned
Bit 1
BL_EN: Backlight Enable Register
0 = Backlight channel is disabled
1 = Backlight channel is enabled
Bit 0
CABC_EN: CABC PWM Input Enable Register
0 = PWM Input is active
1 = PWM Input is inactive (operating at maximum duty cycle)
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Channel number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 8: Backlight and CABC Enable Register.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
23
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
FADE_FLR: Fade In/ Out Floor Levels Register (Address 02h Default 00h)
U-0
U-0
U-0
U-0
W-0
W-0
W-0
W-0
--
--
--
--
FLR[3]
FLR[2]
FLR[1]
FLR[0]
Bit 7
Bit 0
Bit 7 – Bit 4
Unassigned
Bit 3 – Bit 0
FLR<3:0>: Fade In/Out Floor Levels
0000 = 0.45 mA
0001 = 0.90 mA
0010 = 1.80 mA
0011 = 2.70 mA
0100 = 3.60 mA
0101 = 4.50 mA
0110 = 5.40 mA
0111 = 6.30 mA
1000 = 7.20 mA
1001 = 8.10 mA
1010 = 9.00 mA
1011 = 9.90 mA
1100 = 10.8 mA
1101 = 11.7 mA
1110 = 12.6 mA
1111 = 13.5 mA
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Channel number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 9: Backlight Fade In/Out Level Register.
24
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
FADE: Fade In/ Out Control Register (Address 03h Default 03h)
U-0
U-0
U-0
U-0
W-0
--
--
--
--
FTIME[1]
W-0
W-1
W-1
FTIME[0] FADE_EN INIT_FADE
Bit 7
Bit 0
Bit 7 – Bit 4
Unassigned
Bit 3 – Bit 2
FTIME<1:0>: Fade In/Out Timing
00
01
10
11
=
=
=
=
1.0
0.8
0.6
0.4
sec
sec
sec
sec
FADE_EN: Fade In/Out Enable
Bit 1
0 = Fade in/out is enabled for backlight group
1 = Fade in/out is disabled for backlight group
INIT_FADE: Fade In/Out Initiation
Bit 0
0 = Fade out is initiated for backlight group
1 = Fade in is initiated for backlight group
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 10: Backlight Fade In/Out Time and Enable Control Register.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
25
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
ALC_FADE: Ambient Light Control Fade up/down Time and Rate Register
(Address 04h Default 0Bh)
U-0
U-0
U-0
U-0
--
--
--
--
W-1
W-0
W-1
W-1
ALCFU[1] ALCFU[0] ALCFD[1] ALCFD[0]
Bit 7
Bit 0
Bit 7 – Bit 4
Unassigned
Bit 3 – Bit 2
ALCFU<1:0>: Ambient Light Control Fade Up Time and Rate Register
00 = Fade Up Time is 100ms, Fade Up Rate is 0.8ms/step
01 = Fade Up Time is 200ms, Fade Up Rate is 1.6ms/step
10 = Fade Up Time is 400ms, Fade Up Rate is 3.1ms/step
11 = Fade Up Time is 800ms, Fade Up Rate is 6.3ms/step
Bit 1 – Bit 0
ALCFD<1:0>: Ambient Light Control Fade Down Time and Rate Register
00 = Fade Down Time is 50ms, Fade Down Rate is 0.4ms/step
01 = Fade Down Time is 100ms, Fade Down Rate is 0.8ms/step
10 = Fade Down Time is 200ms, Fade Down Rate is 1.6ms/step
11 = Fade Down Time is 400ms, Fade Down Rate is 3.1ms/step
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 11: ALS Fade Up/Down Time and Rate Register.
26
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
ALS_CFG0: Ambient Light Sensor Input Gain Adjustment and Enable Register
(Address 05h Default 10h)
W-0
W-0
W-0
W-1
W-0
W-0
W-0
W-0
PMODE RSET[2] RSET[1] RSET[0] GAIN[1] GAIN[0] GM_SEL ALS_EN
Bit 7
Bit 0
PMODE: Ambient Light Sensor (ALS) Input Gain Polling Mode Selection
Bit 7
0 = Automatic polling mode
1 = Manual polling mode
RSET<2:0>: Ambient Light Sensor (ALS) Set Resistor Selection
Bit 6 – Bit 4
000
001
010
011
=
=
=
=
500Ω, 2kΩ
1kΩ, 4kΩ
2kΩ, 8kΩ
4kΩ, 16kΩ
100 = 8kΩ, 32kΩ
101 = 16kΩ, 64kΩ
110 = Reserved
111 = Reserved
GAIN<1:0>: Ambient Light Sensor (ALS) Input Amplifier Gain Mode Selection
Bit 3 – Bit 2
00 = Low gain mode
01 = High gain mode
1X = Fixed gain mode (External Resistor Required)
Bit 1
GM_SEL: Ambient Light Sensor (ALS) Gain Mode Selection
0 = Auto gain mode
1 = Manual gain mode
Bit 0
ALS_EN: Ambient Light Sensor (ALS) Enable
0 = Disable ambient light sensor
1 = Enable ambient light sensor
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 12: ALS Gain Selection and Enable Register.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
27
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
ALS_CFG1: Ambient Light Sensor (ALS) Voltage Bias Control Register
(Address 06h Default 06h)
W-0
OFF_TM
W-0
W-0
W-0
W-0
OS_ADJ[3] OS_ADJ[2] OS_ADJ[1] OS_ADJ[0]
W-1
W-1
W-0
SB[1]
SB[0]
SB_EN
Bit 7
Bit 0
OFF_TM: Ambient Light Sensor (ALS) Bias Offset Test Mode Enable
Bit 7
0 = Bias offset test mode disable
1 = Bias offset test mode enable
Bit 6 – Bit 3
OS_ADJ<3:0>: Ambient Light Sensor (ALS) Bias Offset Adjustment
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Bit 2 – Bit 1
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
No Adjustment
+1 LSB
+2 LSB
+3 LSB
+4 LSB
+5 LSB
+6 LSB
+7 LSB
-8 LSB
-7 LSB
-6 LSB
-5 LSB
-4 LSB
-3 LSB
-2 LSB
-1 LSB
SB<1:0>: SBIAS Output Voltage Level Selection
00
01
10
11
=
=
=
=
3.0
2.8
2.7
2.6
V
V
V
V
EN_SBIAS: SBIAS Output Enable
Bit 0
0 = Disable SBIAS output
1 = Enable SBIAS output
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 13: ALS Voltage Bias and Offset Calibration Register
28
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
ALS_CFG2: Ambient Light Sensor (ALS) Input Gain Adjustment Register
(Address 07h Default 00h)
W-0
W-0
SNSR
W-0
W-0
W-0
W-0
W-0
W-0
ALSOUT PTIME[1] PTIME[0] G_ADJ[3] G_ADJ[2] G_ADJ[1]G_ADJ[0]
Bit 7
Bit 0
SNSR: Ambient Light Sensor (ALS) Linear or Logarithmic Sensor Output Selection
Bit 7
0 = Linear sensor output
1 = Logarithmic sensor output
ALSOUT: Ambient Light Sensor (ALS) Linear or Logarithmic Backlight Brightness Selection
Bit 6
0 = Linear backlight brightness
1 = Logarithmic backlight brightness
PTIME<1:0>: Ambient Light Sensor (ALS) Input Gain Polling Time Selection
Bit 5 – Bit 4
00
01
10
11
=
=
=
=
0.5
1.0
1.5
2.0
sec
sec
sec
sec
G_ADJ<3:0>: Ambient Light Sensor (ALS) Input Gain Adjustment Selection
Bit 3 – Bit 0
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
No Adjustment
+ 6.25%
+12.50%
+18.75%
+25.00%
+31.25%
+37.50%
+43.75%
-50%
-43.75%
-37.50%
-31.25%
-25.00%
-18.75%
-12.50%
1111 = -6.25%
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 14: ALS Input Gain Adjustment and Polling Time Register.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
29
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
AMLRB: Ambient Light Sensor (ALS) Read Data Register (Address 08h Default 00h)
R
R
AMB[7] AMB[6]
R
R
R
R
R
R
AMB[5]
AMB[4]
AMB[3]
AMB[2]
AMB[1]
AMB[0]
Bit 7
Bit 0
AMB<7:0>: Ambient Light Sensor (ALS) Read Data Register
Bit 7 – Bit 0
00000000 = 00
00000001 = 01
…….
…….
…….
11111111 = 7F
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 15: ALS Digital Output Read Data Register.
30
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
ALS_BLn: Ambient Light Sensor (ALS) Backlight Current Level Programming Register
(Address 09h – Address 18h Default 00h)
W-0
U-0
--
W-0
W-0
ALSn[6] ALSn[5] ALSn[4]
W-0
W-0
W-0
ALSn[3] ALSn[2] ALSn[1] ALSn[0]
Bit 7
Bit 6 – Bit 0
W-0
Bit 0
ALSn<6:0>: Ambient Light Sensor (ALS) Backlight Current Level Programming
LED Current
(Log)
0000100
0000101
0000111
0001001
0001011
0001110
0010001
0010101
0011011
0100010
0101010
0110100
1000001
1010010
1100110
1111111
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
0.00
0.10
0.19
0.29
0.39
0.49
0.58
0.68
0.78
0.88
0.97
1.07
1.17
1.26
1.36
1.46
LED Current
(mA)
0.9
1.1
1.4
1.8
2.3
2.9
3.6
4.5
5.7
7.2
9.0
11.4
14.3
18.0
22.7
28.6
Brightness
(Lux)
64
91
130
185
263
374
532
758
1079
1535
2185
3111
4428
6303
8971
12770
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 16: ALS Controlled Current Dimming Levels Programming Register.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
31
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
LDO_AB: LDOA and LDOB Output Voltage Level Programming Register
(Address 19h Default 00h)
W-0
W-0
W-0
W-0
W-0
W-0
W-0
W-0
LDOA[3] LDOA[2] LDOA[1] LDOA[0] LDOB[3] LDOB[2] LDOB[1] LDOB[0]
Bit 7
Bit 7 – Bit 4
Bit 0
LDOA<3:0>: LDOA Output Voltage Level Selection
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Bit 3 – Bit 0
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
1.2V
1.3V
1.5V
1.6V
1.8V
2.0V
2.2V
2.5V
2.6V
2.7V
2.8V
2.9V
3.0V
3.1V
3.2V
3.3V
LDOB<3:0>: LDOB Output Voltage Level Selection
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
1.2V
1.3V
1.5V
1.6V
1.8V
2.0V
2.2V
2.5V
2.6V
2.7V
2.8V
2.9V
3.0V
3.1V
3.2V
3.3V
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 17: LDOA/LDOB Output Voltage Level Programming Register.
32
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
LDO_CD: LDOC and LDOD Output Voltage Level Programming Register
(Address 1Ah Default 00h)
W-0
W-0
W-0
W-0
W-0
W-0
W-0
W-0
LDOC[3] LDOC[2] LDOC[1] LDOC[0] LDOD[3] LDOD[2] LDOD[1] LDOD[0]
Bit 7
Bit 7 – Bit 4
Bit 0
LDOC<3:0>: LDOC Output Voltage Level Selection
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Bit 3 – Bit 0
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
1.2V
1.3V
1.5V
1.6V
1.8V
2.0V
2.2V
2.5V
2.6V
2.7V
2.8V
2.9V
3.0V
3.1V
3.2V
3.3V
LDOD<3:0>: LDOD Output Voltage Level Selection
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
1.2V
1.3V
1.5V
1.6V
1.8V
2.0V
2.2V
2.5V
2.6V
2.7V
2.8V
2.9V
3.0V
3.1V
3.2V
3.3V
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 18: LDOC/LDOD Output Voltage Level Programming Register.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
33
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
LDO_EN: LDOA/B/C/D Output Enable Register (Address 1Bh Default 00h)
U-0
U-0
U-0
U-0
W-0
W-0
W-0
W-0
--
--
--
--
LDO_END
LDO_ENC
LDO_ENB
LDO_ENA
Bit 7
Bit 7 – Bit 5
Bit 4
Bit 0
Unassigned
LDOD_END : LDOD Output Enable
0 = LDOD output is disabled
1 = LDOD output is enabled
Bit 3
LDOD_ENC : LDOC Output Enable
0 = LDOC output is disabled
1 = LDOC output is enabled
Bit 2
LDOD_ENB : LDOB Output Enable
0 = LDOB output is disabled
1 = LDOB output is enabled
Bit 3
LDOD_ENA : LDOA Output Enable
0 = LDOA output is disabled
1 = LDOA output is enabled
Legend:
R = Readable bit
-v = Default value
W = Writeable bit
‘1’ = Bit is set
U = Unassigned
n = Current Sink number
‘0’ = Bit is cleared
x = Bit is unknown
Figure 19: LDO Output Enable Register.
34
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Ambient Light Sensor (ALS)
An ambient-light sensor is used to measure the brightness of the surrounding environment. Based on the
brightness level, the AAT2893 can adjust the backlight
LED current, leading to longer battery life and comfortable viewing with less eyestrain. The AAT2893 supports
a wide range of sensors, presently on the market, and
performs the gain-adjustment function to correct the
part-to-part output variation of an ambient light sensor.
Some typical values of the luminance in different environments are given below as reference points:
•
•
•
•
•
•
Moonlight: 0.2 to 1 Lux
Candlelight: 5 Lux
Streetlight: 10 Lux
Office light: 300 to 1000 Lux
Daylight (not direct sun): 10,000 Lux
Direct sunlight: 100,000 Lux
Ambient light sensors used in smart phone applications
are often placed underneath a light pipe and a glass
cover. The actual light brightness reaching the ambient
light sensor must be determined before choosing an
ambient light sensor.
Current (mA)
Application Information
Log
r
ea
Lin
Light Intensity (Lux)
Figure 20: Ambient Light Sensor with Linear or
Logarithmic Output Current.
Ambient Light Sensor Evaluation
Determine the Range of Light Brightness
that Reaches Ambient Light Sensor (ALS)
Determine the Type of Ambient Light
Sensor (ALS)-Linear or Logarithmic
Ambient Light Sensor Selection
The types of ambient light sensors on the market include
photodiodes, photo-transistors, and photo-ICs; all these
types of sensors generate current or voltage output signals. Ambient light sensors with current outputs require
a resistor placed at the output to convert the current into
voltage. Figure 20 shows the current output, which is
linear or logarithmic with the light brightness in Lux, of
an ambient- light sensor. Some ambient light sensors
provide logarithmic or square-root outputs. If an ambient light sensor with linear output is used while a logarithmic output is desired, the AAT2893 can convert a
linear ALS output to logarithmic output by setting SNSR
= 0 and setting ALSOUT = 1 in register ALS_CFG2(07h)
as shown in Figure 14.
Ambient Light Sensor Evaluation:
1. Select Gain resistor Set
2. Measure DC Offset
3. Select SBIAS Voltage
4. Determine the LED Current For Each
Brightness Reading
5. Measure Gain Adjustment
Determine the Backlight Brightness
Measurement Mode-Linear or Logarithmic
Determine the Polling Time and Mode –
Automatic or Manual
Figure 21: Ambient Light Sensor Configuration
Flowchart.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
35
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
EN_ALS
ADC
Measurement
500ms for PTIME<1:0> =00
100 ms for
1st Sample
SBIAS
AMB<3:0>
200ms for Manual and Automatic Measurement with AMB_IN ≥ 0.4V (normal ambient brightness)
300ms for Automatic Measurement with AMB_IN < 0.4V (dim ambient brightness)
Figure 22: Ambient Light Sensor A/D Conversion Timing Diagram.
Ambient Light Sensor Gain Resistor Selection
When an ambient light sensor with current output is
selected, a load resistor is used to convert the output
current into an output voltage. The AAT2893 provides a
set of 6 internal resistor pairs that are listed in Figure 12.
An external resistor can be used if none of the integrated
resistor pairs fit the application requirement.
Example 1: The light luminance of the ambient light
sensor is from 0 Lux to 10,000 Lux. If the output current
of an ambient light sensor is 4μA per 100Lux, the resistor required to cover the whole luminance range can be
calculated as follows:
Low-gain Resistor =
VAMB_IN (MAX)
4µA ∙ 10000Lux
100Lux
= 4kΩ
The chosen resistor set is 4kΩ, 16kΩ.
Ambient Light Sensor Offset Adjustment
Any leakage current present will cause an offset at the
output of the ambient light sensor, leading to inaccurate
measurement of the light brightness. This offset can be
corrected by programming bits OS_ADJ<3:0> in register
ALS_CFG1 (06h) of the AAT2893. The four allocated bits
provide offset correction from -8LSB to +7LSB, as shown
in Figure 13.
The DC offset of the ambient-light sensor output can be
36
measured with the AAT2893. The AAT2893 is powered
up and enabled with a power supply or a battery; the
ambient light sensor is then enabled by writing ALS_EN
= 1 to the ALS_CFG0 (05h) register (see Figure 12). The
voltage bias for the ambient light sensor needs to be
enabled as well by writing SB_EN = 1 to the ALS_CFG1
(06h) register (see Figure 13). The test mode of the
ambient light sensor offset commences when writing
OFF_TM = 1 to the ALS_CFG1 (06h) register.
Example 2: The procedure to determine the ambient
light-sensor offset is explained below, assuming a resistor set of 4kΩ, 16kΩ is used:
• Connect the SBIAS pin of the AAT2893 to the input
voltage pin of an ambient light sensor, and connect the
AMB_IN pin of AAT2893 to the output pin of the ambient- light sensor.
• The BH1600FVC ambient light sensor from Rohm is
used with the AAT2893 demo board (Figures 30 and
31). Depending on how much light goes through the
light pipe and reaches the ambient light sensor, the
GC1 and GC2 setting can be determined. If the range
of light is up to 10,000 Lux, the L-Gain mode should
be chosen by connecting GC1 to GND and GC2 to
SBIAS. If the range of light is up to 3,000 Lux or lower,
then the H-Gain mode should be chosen by connecting
GC1 to SBIAS and GC2 to GND. The difference
between H-Gain mode and L-Gain mode is the amount
of output current from the ambient light sensor (see
Table 6).
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
• The AAT2893’s ambient light sensor amplifier is set to
auto gain mode. The part will automatically choose
the 4kΩ low-gain resistor when the ambient light is
bright and the 16kΩ high-gain resistor when the
ambient light is dim for better accuracy.
• Set enable pin EN = High and PWM = High to enable
the AAT2893.
• Start ambient light sensor offset measurement by writing the following commands to the AAT2893:
1. Write AAT2893 7-bit I2C address: 0x60 (first byte
writes as C0h, binary 11000000).
2. Enable backlight channel by writing to register
BL_EN (01h) data 02h.
3. Choose linear ambient light sensor gain mode and
internal gain resistor pair by writing to register
ALS_CFG0 (05h) data 31h.
4. Enable SBIAS in offset test mode by writing to register ALS_CFG1 (06h) data 81h (Note: During normal operation, offset test-mode should be turned
off by setting bit OFF_TM = 0 in ALS_CFG1 (06h)
register as shown in Figure 13).
• Read the AMB (08h) register for the ambient light sensor output offset. AMB register has eight bits, only bits
AMB[7:3] should be captured; bit AMB[7] is a sign (+
or -) bit.
• Convert the 5-bit in AMB(08h) register in test mode to
a 4-bit offset according to Table 3. The 4-bit offset
with opposite sign needs to be written to OS_
ADJ<3:0> from ALS_CFG1 (06h) register during normal operation. Note: If the 5-bit offset reading is F8h
(binary 11111000), then the output offset of the
ambient light sensor is -1LSB. It can be converted to
1111 in 4 bits. In order to adjust this ambient light
sensor offset, a +1 LSB offset needs to be added, by
writing 0001 to OS_ADJ<3:0> of the ALS_CFG1 (06h)
register during normal operation. For complete list of
offset adjustments see Table 2.
ALS_CFG1: Ambient Light Sensor Voltage Bias and Offset Calibration Control Register
ALS 4-Bit Offset Measurement in Test Mode
OS_
ADJ[3]
OS_
ADJ[2]
OS_
ADJ[1]
OS_
ADJ[0]
Offset
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
1
0
1
0
1
0
1
0
+1
+2
+3
+4
+5
+6
+7
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
Offset too high
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
-8
-7
-6
-5
-4
-3
-2
-1
ALS 4-Bit Offset Adjustment in Normal Mode
OS_
ADJ[3]
OS_
ADJ[2]
OS_
ADJ[1]
OS_
ADJ[0]
Offset
0
1
1
1
1
1
1
1
1
0
1
1
1
1
0
0
0
0
0
1
0
1
0
1
0
1
0
0
-1
-2
-3
-4
-5
-6
-7
-8
0
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
0
0
Offset too high
1
1
0
0
0
1
0
1
0
1
0
1
0
1
+7
+6
+5
+4
+3
+2
+1
Table 2: Ambient Light Sensor 4-Bit Offset Adjustment.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
37
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
AMB: Ambient Light Sensor
Digital Output Read Data Register
ALS_CFG1: Ambient Light Sensor
Voltage Bias and Offset Calibration Register
ALS 5-Bit Offset Measurement in Test Mode
ALS 4-Bit Offset Measurement in Test Mode
AMB[7]
AMB[6]
AMB[5]
AMB[4]
AMB[3]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
OS_
ADJ[3]
OS_
ADJ[2]
OS_
ADJ[1]
OS_
ADJ[0]
Offset
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
+1
+2
+3
+4
+5
+6
+7
0
1
0
1
0
1
0
1
-8
-7
-6
-5
-4
-3
-2
-1
Offset too high
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
Table 3: Ambient Light Sensor 5-Bit to 4-Bit Offset Conversion.
38
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Ambient Light Sensor Gain Adjustment
For the majority of ambient light sensors, the part-topart variation of the output current is guaranteed to be
±20% at best. More expensive ambient light sensors can
guarantee ±10% output accuracy. Tolerances in light
pipes and ambient light sensors limit the output current
accuracy to only ±35%. AAT2893 allows the customer to
choose an inexpensive ambient light sensor while offering a ±10% part-to-part variation by providing an automatic calibration gain adjustment from -50% to +43.75%
for any off-the-shelf ambient light sensor. Figure 23
shows the ideal ambient light sensor output versus light
brightness after gain-adjustment calibration.
Part 1
Current (mA)
Ideal
Part 2
The maximum AMB_IN input voltage is 2.4V with -37.5%
gain adjustment. For optimal performance, the minimum
output voltage of an ambient light sensor needs to be
higher than the adjusted AMB_IN input voltage with an
extra 6.25% headroom, or 2.55V according to Table 4.
Ambient Light Sensor Voltage Bias
The external ambient light sensor is powered by the
SBIAS output, which is a programmable linear voltage
regulator that provides up to 30mA for the sensor bias.
The SBIAS output voltage may be programmed and
enabled both by the ambient light sensor control register
ALS_CFG0 (Figure 12) and the ambient light sensor voltage bias control register ALS_CFG1 (Figure 13). The
SBIAS voltage can be selected from 2.6V up to 3V by
writing bits SB<1:0> of the ALS_CFG1 (06h) register.
The SBIAS voltage is determined based on the full-scale
negative gain adjustment necessary to achieve optimal
performance. The relationship between the AMB_IN ideal
Full-Scale voltage (unadjsted Full-Scale), the gain
adjustment (Gain_ADJ), and the adjusted AMB_ IN scale
(Adjusted Full-Scale) can be expressed by the following
equation:
Adjusted Full-Scale =
Light Intensity (Lux)
Figure 23: Ambient Light Sensor Output Current
with Gain Variation.
Ideal Full-Scale
1 + Gain_ADJ
The minimum saturated output voltage of the BH1600FVC
ambient light sensor is 2.6V for 3.0V supply voltage;
therefore, a SBIAS voltage of 3V should be selected for
this particular case. If the calculated AMB_IN maximum
voltage exceeds 3V, an external voltage source is recommended.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
39
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
G_ADJ[3:0]
Gain Adjustment
(%)
AMB_IN Full
Scale (V)
ALS_CFG2 (07h)
AMB_IN Min
(V)
AMB_IN Max
(V)
0111
0110
0101
0100
0011
0010
0001
0000
1111
1110
1101
1100
1011
1010
1001
1000
43.75
37.50
31.25
25.00
18.75
12.50
6.25
0
-6.25
-12.5
-18.75
-25.00
-31.25
-37.50
-43.75
-50.00
1.11
1.16
1.22
1.28
1.35
1.42
1.51
1.60
1.71
1.83
1.97
2.13
2.33
2.56
2.84
3.20
07h
06h
05h
04h
03h
02h
01h
00h
0Fh
0Eh
0Dh
0Ch
0Bh
0Ah
09h
08h
1.04
1.09
1.14
1.20
1.26
1.33
1.41
1.50
1.60
1.71
1.85
2.00
2.18
2.40
2.67
3.00
1.18
1.24
1.30
1.36
1.43
1.51
1.60
1.70
1.81
1.94
2.09
2.27
2.47
2.72
3.02
3.40
Table 4: Ambient Light Sensor Gain Adjustment.
Backlight LED Current Settings for Different
Brightness Readings
The main recipient of the light emitted by all visible
spectrum LEDs is the human eye. It responds to light
luminance in a non-linear, logarithmic way. The sensitivity of the human eye decreases rapidly as the luminance
of the source increases. The LED current needs to
change logarithmically in relation to the light brightness
in order for the light brightness to be perceived linearly
by the human eye.
The AAT2893 has sixteen default LED current setting
levels programmed in ALSn (from 09h to 18h) registers.
These sixteen current level settings follow the logarithmic trend shown in Figure 24. A linear ambient light
sensor output and a linear output brightness are set by
using the default setting of SNSR=0 and ALSOUT=0 of
the ALS_CFG2 (07h) register. For each light brightness
sampling, one of the current levels corresponding to the
ambient light reading will be selected to control the
backlight LED current. If the desired current settings are
different than the default, the user can change them by
writing to ALSn (09h through 18h) registers.
LED Current (mA)
100
10
1
0.1
0.1
1
10
100
1000
10000 100000
Brightness (Lux)
Figure 24: Backlight LED Current vs Light Brightness.
40
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
AAT2893 allows automatic and manual modes for measurement of the ambient light sensor brightness. The
automatic gain mode is selected by default value GM_
SEL = 0 in ALS_CFG0 (05h) register. For better accuracy
during automatic mode, the AAT2893 will choose low
gain resistor when the ambient light is bright and high
gain resistor when the ambient light is dim. For the
manual gain mode, all light brightness measurements
are completed with the low gain resistor as set by GM_
SEL = 1 of the ALS_CFG0 (05h) register.
Ambient Light Sensor Brightness Polling Time
The AAT2893 offers two bits for programming the ambient light sensor brightness polling time. There are four
different polling times: 0.5s, 1s, 1.5s and 2s selected by
writing PTIME<1:0> bits of the ALS_CFG2 (07h) register.
If an automatic ambient light sensor polling mode is
selected by default PMODE = 0 of ALS_CFG0 (05h) register, the AAT2893 will periodically update the information about the surrounding brightness at an interval of
every elapsed time. Refer to Figure 22 for A/D conversion timing diagram. Manual ambient sensor polling
mode can also be selected by writing PMODE = 1 to
ALS_CFG0 (05h) register.
Mode
GC1
GC2
Current
µA/100Lux
H-Gain Mode
L-Gain Mode
1
0
0
1
60
6.31
Table 6: Rohm BH1600FVC Ambient Light Sensor
Output Current Level.
Parameter
Value
Maximum Brightness (Lux)
Floor Brightness (Lux)
ALS Output (μA/10 Lux)
Gain Resistor (KΩ)
Gain Adjustment (%)
AMB-IN Full-Scale (V)
Maximum. LED Current (mA)
Floor Current (mA)
Brightness / Floor
Log (Brightness / Floor)
Log current per level
Brightness / Level
k factor
10000
64
0.63
4
-18.75
1.92
28.60
0.9
156.25
2.19
0.10
662.4
0.68
Table 7: Determination of LED Current vs
Brightness in a Logarithmic Relationship.
Eq.1:
log
15
AAT2893 Programming Examples
Example 1: Ambient Light Sensor Linear Brightness
Readings and Logarithmic Backlight Response
SNSR = 0: Linear Measurement
ALSOUT = 0: Linear Output
Backlight Current: Logarithmic Response
Brightness (Lux)
LED Current (mA)
1--64
64--10000
0.9
0.9 to 28.6 in log scale
Table 5: Sensor Requirements for Example 1.
Ambient light sensor model BH1600FVC from Rohm is
used for all examples:
(Brightness
Floor
(
Ambient Light Sensor Brightness Gain Mode
= 0.15
Setup Description:
Ambient light sensor model BH1600FVC from Rohm is
used with the AAT2893 demo board (Figures 30 and 31).
The demo board jumper P3 controls the gain setting GC2
and jumper P4 controls the gain setting GC1. Pin 1 (logic
1) on the jumpers P3 and P4 is designated by the square
pad in Figure 28.
• Select low gain ALS output (GC1 = 0, GC2 = 1)
• Backlight LED Current=28.6mA is selected, or doesn't
need to be set
• Resistor set of 4KΩ, 16KΩ is calculated for the application
• Enable Backlight channel. (BL_EN = 1)
• Ambient light sensor has no DC offset
• Ambient light sensor gain adjustment is -18.75%
• Linear ALSOUT and SNSR are selected
• SBIAS = 3.0V is selected
• Enable Ambient Light Sensor. (ALS_EN = 1)
• Light brightness is measured at 1s time intervals
• Read register AMLRB (08h).
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
41
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
• Default settings are used for ALS_BLn (09h to 18h)
registers.
The following commands need to be communicated to
the AAT2893 through the I2C interface:
• Write AAT2893 7-bit I2C address: 0x60 (first byte
writes as C0h; binary 11000000)
• Write to register BL_ENBLS (01h) data 02h
ALS_BLn
(09h 18h)
Light
Brightness
(Lux)
Log of
Current/
Floor of
Each Level
LED
Curent
(mA)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
64
726
1389
2051
2714
3376
4038
4701
5363
6026
6688
7350
8013
8675
9338
10000
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
1.40
1.50
0.9
1.1
1.4
1.8
2.3
2.9
3.6
4.5
5.7
7.2
9.0
11.4
14.3
18.0
22.7
28.6
•
•
•
•
Write to register ALS_CFG0 (05h) data 31h
Write to register ALS_CFG1 (06h) data 01h
Write to register ALS_CFG2 (07h) data 1Dh
Read register AMLRB (08h); bits AMB[7:0] indicate the
ambient light brightness level; first byte writes as
C1h; all readings are listed in Table 8. AMB[7] is the
sign (+ or -) bit.
Register Data
AMB_IN
Voltage (mV)
Register
Address
(Hex)
(Dec)
(Hex)
(Binary)
13.10
148.73
284.36
419.98
555.61
691.24
826.86
962.49
1098.12
1233.74
1369.37
1504.99
1640.62
1776.25
1911.87
2047.50
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
4
5
6
8
10
13
16
20
25
32
40
51
64
80
101
127
4h
5h
6h
8h
Ah
Dh
10h
14h
19h
20h
28h
33h
40h
50h
65h
7Fh
0000100
0000101
0000110
0001000
0001010
0001101
0010000
0010100
0011001
0100000
0101000
0110011
1000000
1010000
1100101
1111111
Table 8: Ambient Light Sensor Linear Brightness Readings and Logarithmic Backlight Response.
Example 2: Ambient Light Sensor Linear Brightness
Readings and Linear Backlight Response
SNSR = 0: Linear Measurement
ALSOUT = 0: Linear Output
Backlight Current: Linear Response
Brightness (Lux)
LED Current (mA)
1--40
40--10000
5
5 to 20
Table 9: Sensor Requirements for Example 2.
42
Parameter
Value
Maximum Brightness (Lux)
Floor Brightness (Lux)
ALS Output (μA/10Lux)
Gain Resistor (kΩ)
Gain Adjustment (%)
AMB-IN Full-Scale (V)
Maximum. LED Current (mA)
Floor Current (mA)
Brightness / Level (Lux)
LED Current per Level
10000
40
0.63
4
-18.75
1.92
20
5
664
1
Table 10: Determination of LED Current vs
Brightness in a Logarithmic Relationship.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
GC2
GC1
Mode
0
0
1
0
1
0
1
1
Shutdown
H-Gain Mode
L-Gain Mode
Test Mode (input
prohibition)
Table 11: Rohm BH1600FVC Ambient Light Sensor
Mode Settings.
Setup Description:
Ambient light sensor model BH1600FVC from Rohm is
used with the AAT2893 demo board (Figures 30 and 31).
The demo board jumper P3 controls the gain setting GC2
and jumper P4 controls the gain setting GC1.
• Select low gain ALS output (GC1 = 0, GC2 = 1) (see
Table 11)
• Resistor set of 4kΩ, 16kΩ is calculated for the application
• Enable backlight channel (BL_EN = 1)
• Ambient light sensor has no DC offset
• Ambient light sensor gain adjustment is -18.75%
• Linear ALSOUT and SNSR are selected
• SBIAS = 3.0V is selected
• Enable Ambient Light Sensor. (ALS_EN = 1)
• Light brightness is measured at an interval of 1s
• Read register AMLRB (08h)
• Write the data to ALS_BLn (09h to 18h) registers
The following commands need to be communicated to
AAT2893 through I2C:
• Write AAT2893 7-bit I2C address:
0x60 (binary 11000000, first byte writes as C0h)
• Write to register BL_ENBLS (01h) data 02h
• Write to register ALS_CFG0 (05h) data 31h
• Write to register ALS_CGF1 (06h) data 01h
• Write to register ALS_CFG2 (07h) data 1Dh
• Read register AMLRB (08h); bits AMB[7:0] indicate the
ambient light brightness level; first byte writes as
C1h; all readings are listed in Table 12
• Write to register ALS_BL0 (09h) data 16h
• Write to register ALS_BL1 (0Ah) data 1Bh
• Write to register ALS_BL2 (0Bh) data 1Fh
• Write to register ALS_BL3 (0Ch) data 24h
• Write to register ALS_BL4 (0Dh) data 28h
• Write to register ALS_BL5 (0Eh) data 2Ch
• Write to register ALS_BL6 (0Fh) data 31h
• Write to register ALS_BL7 (10h) data 35h
• Write to register ALS_BL8 (11h) data 3Ah
• Write to register ALS_BL9 (12h) data 3Eh
• Write to register ALS_BLA (13h) data 43h
• Write to register ALS_BLB (14h) data 47h
• Write to register ALS_BLC (15h) data 4Ch
• Write to register ALS_BLD (16h) data 50h
• Write to register ALS_BLE (17h) data 54h
• Write to register ALS_BLF (18h) data 59h
ALS_BLn
(09h - 18h)
Light
Brightness
(Lux)
LED
Curent
(mA)
AMB_IN
Voltage (mV)
Register
Address
(Hex)
Register Data
(Dec)
(Hex)
(Binary)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
40
704
1368
2032
2696
3360
4024
4688
5352
6016
6680
7344
8008
8672
9336
10000
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
16.0
17.0
18.0
19.0
20.0
8.19
144.14
280.10
416.05
552.01
687.96
823.91
959.87
1095.82
1231.78
1367.73
1503.68
1639.64
1775.59
1911.55
2047.50
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
22
27
31
36
40
44
49
53
58
62
67
71
76
80
84
89
16h
1Bh
1Fh
24h
28h
2Ch
31h
35h
3Ah
3Eh
43h
47h
4Ch
50h
54h
59h
0010110
0011011
0011111
0100100
0101000
0101100
0110001
0110101
0111010
0111110
1000011
1000111
1001100
1010000
1010100
1011001
Table 12: Ambient Light Sensor Linear Brightness Readings and Linear Backlight Response.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
43
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Example 3: Ambient Light Sensor Logarithmic Brightness
and Logarithmic Backlight Response
SNSR = 0: Linear Measurement
ALSOUT = 1: Logarithmic Output
Backlight Current: Logarithmic Response
Brightness (Lux)
LED Current (mA)
1--10
10--100
100--1000
1000--10000
5
10
15
20
Table 13: Sensor Requirements for Example 3.
Parameter
Value
Maximum Brightness (Lux)
Floor Brightness (Lux)
ALS Output (μA/10Lux)
Gain Resistor (kΩ)
Gain Adjustment (%)
AMB-IN Full-Scale (V)
Maximum. LED Current (mA)
Floor Current (mA)
Brightness/Floor
Log(Brightness/Floor)
Log current per level
k factor
1000
40
6
4
-18.75
1.92
20
5
25
1.40
0.04
0.43
Table 14: Determination of LED Current vs
Brightness in a Logarithmic Relationship.
log
(Brightness
Floor
15
(
Eq 2:
= 0.09
Setup Description:
Ambient light sensor model BH1600FVC from Rohm is
used with the AAT2893 demo board (Figures 30 and 31).
The demo board jumper P3 controls the gain setting GC2
and jumper P4 controls the gain setting GC1.
44
• Select high gain ALS output (GC1 = 1, GC2 = 0) (see
Table 11).
• Resistor set of 4kΩ, 16kΩ is calculated for the application
• Enable backlight channel (BL_EN = 1)
• Ambient light sensor has no DC offset
• Ambient light sensor gain adjustment is -18.75%
• Logarithmic ALSOUT and Linear SNSR are selected
• SBIAS = 3.0V is selected
• Light brightness is measured at an interval of 1s time
• Read register AMLRB (08h)
• Write to registers ALS_BLn (09h to 18h) the data
The following commands need to be communicated to
AAT2893 through I2C:
• Write AAT2893 7-bit I2C address: 0x60
(binary 11000000; first byte writes as C0h)
• Write to register BL_ENBLS (01h) data 02h
• Write to register ALS_CFG0 (05h) data 31h
• Write to register ALS_CFG1 (06h) data 01h
• Write to register ALS_CFG2 (07h) data 5Dh
• Read register AMLRB (08h); bits AMB[7:0] indicate the
ambient light brightness level; first byte writes C1h;
all readings are listed in Table 15.
• Write to register ALS_BL0 (09h) data 16h
• Write to register ALS_BL1 (0Ah) data 1Bh
• Write to register ALS_BL2 (0Bh) data 1Fh
• Write to register ALS_BL3 (0Ch) data 24h
• Write to register ALS_BL4 (0Dh) data 28h
• Write to register ALS_BL5 (0Eh) data 2Ch
• Write to register ALS_BL6 (0Fh) data 31h
• Write to register ALS_BL7 (10h) data 35h
• Write to register ALS_BL8 (11h) data 3Ah
• Write to register ALS_BL9 (12h) data 3Eh
• Write to register ALS_BLA (13h) data 43h
• Write to register ALS_BLB (14h) data 47h
• Write to register ALS_BLC (15h) data 4Ch
• Write to register ALS_BLD (16h) data 50h
• Write to register ALS_BLE (17h) data 54h
• Write to register ALS_BLF (18h) data 59h
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
ALS_BLn
(09h 18h)
Light
Brightness
(Lux)
Log of
Brightness
/ Floor
Level
LED
Curent
(mA)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
40
50
61
76
94
117
145
180
223
276
342
424
525
651
807
1000
0
0.09
0.19
0.28
0.37
0.47
0.56
0.65
0.75
0.84
0.93
1.03
1.12
1.21
1.30
1.40
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
16.0
17.0
18.0
19.0
20.0
Register Data
AMB_IN
Voltage (mV)
Register
Address
(Hex)
(Dec)
(Hex)
(Binary)
78.00
96.67
119.81
148.49
184.03
228.07
282.66
350.32
434.17
538.09
666.89
826.51
1024.35
1269.53
1573.40
1950.00
09h
0Ah
0Bh
0Ch
0Dh
0Eh
0Fh
10h
11h
12h
13h
14h
15h
16h
17h
18h
22
27
31
36
40
44
49
53
58
62
67
71
76
80
84
89
16h
1Bh
1Fh
24h
28h
2Ch
31h
35h
3Ah
3Eh
43h
47h
4Ch
50h
54h
59h
0010110
0011011
0011111
0100100
0101000
0101100
0110001
0110101
0111010
0111110
1000011
1000111
1001100
1010000
1010100
1011001
Table 15: Ambient Light Sensor Logarithmic Brightness Readings and Logarithmic Backlight Response.
Content Adaptive Brightness Control
(CABC)
The CABC response to an external PWM signal is set by
the filter capacitor, CFLTR, connected to the FLTR pin. In
order to select CFLTR properly, three conditions need to be
known:
1. PWM signal frequency at the PWM pin
2. The desired rate of change of the backlight current
from one level to another
3. The minimum PWM duty cycle.
The capacitor (CFLTR) connected to the FLTR pin has an
internal resistor RF = 73.3kΩ in parallel with ground. The
filter capacitor CFLTR pin is charged with a 20μA current
source that is modulated with the PWM duty cycle. Refer
to Figures 25 and 26 for circuit and timing diagrams.
The value for CFLTR can be calculated with the following
equation:
tF
3 ∙ RF ∙ ln
(D0
D1
(
CFLTR =
Where,
and
D0 is the PWM Duty Cycle before the adjustment
D1 is the PWM Duty Cycle after the adjustment.
If the selected CFLTR capacitor value is smaller than 5nF,
then the ripple appearing on the backlight PWM current
will increase. For external PWM signals equal or lower
than 10% duty cycle, the bottom level of the ripple can
cause the internal comparators to trip and as a result,
the part will switch to a maximum duty cycle of 97.8%
for a few clock periods.
If the selected CFLTR value is large, the ripple on the backlight PWM current will be reduced, but it may not be
possible to achieve a fast change (tF) of the backlight
current level or the desired duty cycle. Table 16 shows
the recommended CFLTR Value for Different tF.
If the CABC function is not desired it can be disabled by
changing bit CABC from 0 to 1 in BL_ENBLS (01h) register. The AAT2893 will operate with a maximum duty cycle
of 97.8% and the CFLTR capacitor is not necessary.
CFLTR (nF)
tF (ms)
6.8
10
22
33
47
68
100
220
1.5
2.8
3.6
5.1
6.9
10.2
18
40
Table 16: Recommended CFLTR Value for Different
tF.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
45
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
VIN
External PWM
Control Input
20μA
PWM
ILED
I2C & ALS
Control
VFLTR
RF
73.3kΩ
FLTR
CF
Figure 25: CABC Circuit Diagram.
tF
ILED
0
Time
Figure 26: CABC Timing.
Note: A small value CFLTR will result in faster transition time (tF) between current levels but is limited to 5nF by the backlight PWM current ripple.
46
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
LED Selection
PWM Duty Cycle vs WLED Current
(11 WLEDs)
30
25
ILED (mA)
The AAT2893 is specifically designed for driving white
LEDs in TFT-LCD backlighting applications but the device
design allows the AAT2893 to drive most types of LEDs
with forward voltage specifications ranging from 2.0V to
4.7V. LED applications may include mixed arrangements
for display backlighting, color (RGB) LEDs, infrared (IR)
diodes or any other load needing a constant current
source generated from a varying input voltage.
ILED vs Efficiency
(11 WLEDs)
85
80
Efficiency (%)
75
VIN = 3.6V
VIN = 4.2V
VIN = 5.0V
VIN = 5.5V
0
10
20
30
40
50
60
70
80
90
100
PWM Duty (%)
Figure 28: PWM Duty Cycle vs WLED Current at
11 WLEDs Application.
Input Voltage vs Max WLED Current
(AAT2893 - 1)
30
29
28
27
26
11 WLEDs
25
24
23
22
21
70
20
65
3
60
VIN = 3.0V
55
VIN = 3.6V
3.5
3.75
4
4.25
4.5
4.75
5
5.25
5.5
Input Voltage (V)
VIN = 5.0V
45
3.25
Figure 29: Input Voltage vs Max WLED Current at
11 WLEDs Application.
VIN = 4.2V
50
40
VIN = 3.0V
10
0
Max. ILED (mA)
The maximum number of WLED depends on the OVP of
the AAT2893 part and the forward voltage (VF) of WLED.
The OVP of AAT2893-1 is 42V, to a general WLED with
about 3.3V forward voltage, it means AAT2893 has ability to drive more than 10 LEDs in series. Figure 27, 28
and 29 show the efficiency, PWM duty vs WLED current
and WLED current at different input voltage when
AAT2893 drive 11 WLEDs.
15
5
The low-dropout current sinks in the AAT2893 maximize
performance and make it capable of driving LEDs with
high forward voltage.
Driving 11 WLEDs Application
20
VIN = 5.5V
0
5
10
15
20
25
30
ILED (mA)
Figure 27: WLED Current vs Efficiency at 11
WLEDs Application.
Inductor Selection
Inductor value, saturation current and DCR are the most
important parameters in selecting an inductor for the
AAT2893.
The suitable inductance range for the AAT2893 is 4.7μH
to 22μH. Higher inductance lowers the step-up converter's RMS current value. Together with lower DCR value
of the inductor, it makes the total inductor power loss
become much lower. Considering inductor size and cost,
4.7μH inductance is most suitable.
Considering the inductor copper loss, the inductor DCR
value together with the RMS current flowing through the
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
47
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
inductor leads to inductor conduction loss and also
affects total efficiency. Larger DCR leads to larger conduction loss and reduces total efficiency. The inductor
conduction loss can be estimated using the following
equation:
(I2L_MAX + I2L_MIN + IL_MAX ∙ IL_MIN) ∙ DCR
PL_LOSS = I2L_RMS ∙ DCR =
3
Where IL_MAX and IL_MIN are the inductor peak current and
minimum current respectively.
Inductor saturation current is also a key parameter in
selecting an inductor. For the step-up converter, the peak
inductor current is the DC input current plus half the
inductor peak-to-peak current ripple.
DC input current:
VOUT ∙ ILED
IIN =
IL_PP
VIN ∙ (VOUT - VIN)
2
=
VOUT ∙ L ∙ f
VOUT ∙ ILED
VIN ∙ η
+
VIN ∙ (VOUT - VIN)
2 ∙ VOUT ∙ L ∙ f
For example, for a white LED with 3.2V VF, 20mA current, 81% efficiency and VIN less than 3.6V, the inductor
peak current is:
IL_PEAK =
3.2 ∙ 8 ∙ 0.02
3.6 ∙ (3.2 ∙ 8 - 3.6)
= 330mA
+
3.6 ∙ 0.81
2 ∙ 3.2 ∙ 8 ∙ 10μ ∙ 1M
Compensation Component Selection
A compensation capacitor CCOM is used for step-up converter loop compensation and soft startup time control.
Loop compensation requires matching values for CCOM,
COUT, ILED, and VOUT:
COUT
CCOM
48
<
ILED (nF)
=
(1 ∙ 30 ∙ 40)
30(nF)
= 40(nF)
A higher value for CCOM lengthens the soft startup time.
So to balance the startup time and the loop stability,
56nF is selected. The relationship between CCOM and
startup time is almost linear, with startup time x 105
magnification of CCOM; thus 56nF CCOM leads to a soft
startup time of 5.6ms. Values of 56nF for CCOM and 1μF
for COUT are suitable in most cases.
To achieve maximum efficiency, a low VF Schottky diode
is recommended. For an AAT2893 driving 10 white LEDs
with up to 4V forward voltage, the diode voltage rating
should be higher than 40V. Selecting a diode with DC
rated current being equal to the input current allows an
adequate margin for safe use.
Inductor peak current:
IL_PEAK = IIN +
CCOM > (COUT ∙30 ∙ VOUT)
Schottky Diode Selection
VIN ∙ η
Inductor peak-to-peak current ripple:
IL_PP =
For example, considering the worse case of AAT2893
driving 10 white LEDs with forward voltages 4V, a COUT
value of 1μF, and LED maximum current of about 30mA,
the value of CCOM should be higher than 40nF.
ILED
30 ∙ 10-6 ∙ VOUT
Printed Circuit Board Layout
Recommendations
Boost converter performance can be adversely affected
by poor layout. Possible impact includes high input and
output voltage ripple, poor EMI performance, and
reduced operating efficiency. Every attempt should be
made to optimize the layout in order to minimize parasitic effects on PCB (stray resistance, capacitance, and
inductance) and EMI coupling at the high frequency
switching node. A suggested PCB layout for the AAT2893
is shown in Figures 31. The following PCB layout guidelines should be considered:
1.Place the input and output decoupling capacitors C1,
C3, C5, C2, C4, C8, C9 as close to the chip as possible
to reduce switching noise and output ripple.
2.Keep the power traces (GND, LX VOUT and VIN) short,
direct, and wide to allow large current flow. Place sufficient multiple-layer pads, when needed, to change
the trace layer.
3.Maintain a ground plane and connect to the IC PGND
pin(s) as well as the PGND connections of CIN and COUT.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Schematic and Layout
1
3
5
7
9
ILED
D1
E3
E2
COMP
LDOD
C2
4.7µF
B1
A4
2
4
6
8
10
AMB_ IN
Gnd
SDA
TP9
SBIAS
TP4
A2
C8
2.2µF
A1
C9
2.2µF
GND
LDOC
TP5
LDOD
SBIAS
GC2
R13
0Ω
1
R10
(open)
2
Header 5X 2
C10
2.2µF
C4
2.2µF
A3
DGND
LDOC
TP3
LDOB
TP6
P5
SCL
LDOB
FLTR
B4
PWM
R2
0Ω
LDOA
C3
2.2µF
LDOA
U1
AAT2893
PWM
TP2
VIN
C2
E4
C6
56nF
EN
D6
JP3
IN _LDO
SDA
•
D4
JP2
D3
VIN
C7
10nF
D7
SDA
P2
D2
•
•
D8
SCL
R11
100kΩ
PWM
D9
C3
EN
D10
JP1
SCL
R9 100kΩ
PWM
D11
IN
AMB_IN
B3
TP10
OUT
E1
LX
B2
VIN
D5
• •
SDM20U40
SBIAS
P1
D4
C1
•
C1
4.7µF
VIN
D3
•
DS1
C4
TP1
D2
PGND
L1
4.7µH
D1
AGND
C5
2. 2µF
R12
0Ω
3
U2
OUT
GC2
GND
GC1
VCC
NC
P3
GC2
6
5
4
BH1600FVC
SBIAS
GC1
P4
GC1
GND
Figure 30: AAT2893 WLCSP-20 Evaluation Board Schematic.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
49
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Figure 31: AAT2893 Evaluation Board Top and Bottom Side Layout.
Figure 32: AAT2893 Evaluation Board WLCSP-20 package Top and Bottom Side Layout.
50
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Component
Part Number
U1
AAT2893IUL
U2
C1,C2
C3, C4, C8, C9,
C10
C5
C6
C7
D1-D10
D11
DS1
L1
P5
R2,R13, R12
R9, R11
R10
BH1600FVC
GRM188R60J475K
GCM188R70J225KE22
GRM21BR61H225KA73L
GRM188R71C563K
GRM188R71H103KA01
RS-0805UW
SDM20U40
CDRH3D14-4R7NC
Chip Resistor
Description
Ambient Light Control Boost LED Backlight Driver IC
with 4 LDOs; WLCSP20
Ambient Light Sensor IC; WSOF6
Cap Ceramic 4.7μF 0603 X5R 6.3V 10%
Manufacturer
Skyworks
Rohm
2.2μF, 6.3V, X7R, 0603
2.2μF, 50V, X7R, 0805
Cap Ceramic 0.056μF 0603 X7R 16V 10%
10nF, 50V, X7R, 0603
30mA White LED 0805
Not populated. Do not solder
Surface Mount Schottky Barrier Diode
Power Inductor 4.7μH 1.1A SMD
0.1" Header, 2x5 pins
0Ω, 1%, 1/8W; 0402
100kΩ, 1%, 1/4W; 0603
Open, reserved for external Gain Resistor adjust
Murata
Realstar
Diodes
Sumida
Vishay
Table 16: AAT2893 Evaluation Board Bill of Materials (BOM).
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
51
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Ordering Information
Package
Marking1
OVP
Part Number (Tape and Reel)2
WLCSP-20
WLCSP-20
V9YW
W5YW
42V
33V
AAT2893IUL-1-T1
AAT2893IUL-2-T1
Skyworks Green™ products are compliant with
all applicable legislation and are halogen-free.
For additional information, refer to Skyworks
Definition of Green™, document number
SQ04-0074.
Package Information
WLCSP-20
D1
0.650
0.200
0.380
0.070
2.625
2.095
1.600 BSC
1.200 BSC
N/A
0.200 BSC
0.400 BSC
0.265
0.200
0.200
20 Balls
0.735
0.225
0.405
0.105
2.660
2.130
+
+
+
+
4
+
+
+
+
+
3
+
+
+
+
+
2
+
+
+
+
+
1
E
D
C
D
B
A
(Bottom View)
0.290
-
A3
A
(Side View)
Y1
NxØb
X1
0.240
0.600
0.600
-
+
A2
X X
LINE_1
Y W
LINE_2
1/2 E
0.565
0.175
0.355
0.035
2.590
2.060
A1
X
A
A1
A2
A3
D
E
D1
E1
SD
SE
e
b
X
Y
X1
Y1
N
e
E
Max
e
Nominal
E1
Min
SE
Symbol
Y
All dimensions in millimeters.
(Side View)
LDOD
1/2 D
XX: V9 - 42V
XX: W5 - 33V
Ø 0.2 (Ref.)
PIN A1 Indication
(Top View)
1. YW = Year and week code.
2. Sample stock is generally held on part numbers listed in BOLD.
52
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
DATA SHEET
AAT2893
CABC Compatible, Ambient Light Control Boost LED Backlight Driver and Four LDOs
Copyright © 2012 Skyworks Solutions, Inc. All Rights Reserved.
Information in this document is provided in connection with Skyworks Solutions, Inc. (“Skyworks”) products or services. These materials, including the information contained herein, are provided by Skyworks as a
service to its customers and may be used for informational purposes only by the customer. Skyworks assumes no responsibility for errors or omissions in these materials or the information contained herein. Skyworks may change its documentation, products, services, specifications or product descriptions at any time, without notice. Skyworks makes no commitment to update the materials or information and shall have no
responsibility whatsoever for conflicts, incompatibilities, or other difficulties arising from any future changes.
No license, whether express, implied, by estoppel or otherwise, is granted to any intellectual property rights by this document. Skyworks assumes no liability for any materials, products or information provided hereunder, including the sale, distribution, reproduction or use of Skyworks products, information or materials, except as may be provided in Skyworks Terms and Conditions of Sale.
THE MATERIALS, PRODUCTS AND INFORMATION ARE PROVIDED “AS IS” WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, INCLUDING FITNESS FOR A PARTICULAR
PURPOSE OR USE, MERCHANTABILITY, PERFORMANCE, QUALITY OR NON-INFRINGEMENT OF ANY INTELLECTUAL PROPERTY RIGHT; ALL SUCH WARRANTIES ARE HEREBY EXPRESSLY DISCLAIMED. SKYWORKS DOES
NOT WARRANT THE ACCURACY OR COMPLETENESS OF THE INFORMATION, TEXT, GRAPHICS OR OTHER ITEMS CONTAINED WITHIN THESE MATERIALS. SKYWORKS SHALL NOT BE LIABLE FOR ANY DAMAGES, INCLUDING BUT NOT LIMITED TO ANY SPECIAL, INDIRECT, INCIDENTAL, STATUTORY, OR CONSEQUENTIAL DAMAGES, INCLUDING WITHOUT LIMITATION, LOST REVENUES OR LOST PROFITS THAT MAY RESULT FROM
THE USE OF THE MATERIALS OR INFORMATION, WHETHER OR NOT THE RECIPIENT OF MATERIALS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Skyworks products are not intended for use in medical, lifesaving or life-sustaining applications, or other equipment in which the failure of the Skyworks products could lead to personal injury, death, physical or environmental damage. Skyworks customers using or selling Skyworks products for use in such applications do so at their own risk and agree to fully indemnify Skyworks for any damages resulting from such improper
use or sale.
Customers are responsible for their products and applications using Skyworks products, which may deviate from published specifications as a result of design defects, errors, or operation of products outside of published parameters or design specifications. Customers should include design and operating safeguards to minimize these and other risks. Skyworks assumes no liability for applications assistance, customer product
design, or damage to any equipment resulting from the use of Skyworks products outside of stated published specifications or parameters.
Skyworks, the Skyworks symbol, and “Breakthrough Simplicity” are trademarks or registered trademarks of Skyworks Solutions, Inc., in the United States and other countries. Third-party brands and names are for
identification purposes only, and are the property of their respective owners. Additional information, including relevant terms and conditions, posted at www.skyworksinc.com, are incorporated by reference.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [email protected] • www.skyworksinc.com
202075B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • September 4, 2012
53