SM8133B
White LED Driver IC
OVERVIEW
The SM8133B is a charge pump type white LED driver. It can drive 1 to 6 backlight white LED connected in
parallel and 1 flash white LED. The output voltage circuit has a 3.0V LDO (Low Dropout Regulator), making
the device ideal for camera-equipped cellular phones. The charge pump switches between
×1
to
×1.5
boost
mode in response to LED drive current requirements to extend battery life to the maximum. The boost switch-
ing occurs in response to the drive current of all the connected LED and thus supports variations in LED for-
ward-bias voltage drop (VF). Each LED drive current is controlled by a 7-channel LED drive current control
circuit. The 6 backlight channels can be subdivided into 2 groups, with each group having independent dim-
ming and lighting control. The backlight grouping, backlight LED drive current and ON/OFF control, flash
LED drive current and ON/OFF control, and LDO output ON/OFF control are all set by 3-wire serial interface
data input. Also, the RESETB pin can be connected to the microcontroller supply for a system-wide shutdown
function.
FEATURES
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Noise reduction due to charge pump boost circuit
Automatic charge pump switching to conserve
power
Drives 1 to 6 backlight white LED
(30mA/ch at maximum setting)
Drives a flash white LED
(150mA at maximum setting)
Backlight and flash white LED brightness
adjustment
Group settings for 2-group backlight lighting
control
3-wire serial input interface for all setting and
control
3.0V output LDO circuit built-in
Shutdown function by RESETB pin
Soft start circuit built-in
Thermal protection circuit built-in
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Input voltage range
• No-load current (I
OUT
= 0mA): 2.7 to 4.6V
• Load current (I
OUT
= 80mA): 3.0 to 4.6V
• Load current (I
OUT
= 200mA): 3.3 to 4.6V
Quiescent current
• LDO only: 0.3mA (typ)
• Not -switching (×1.0 mode): 0.5mA (typ)
• Switching (
×
1.5 mode): 2.5mA (typ)
Standby current: 0.01µA (typ)
Operating frequency: 750kHz (typ)
Backlight LED current: 30mA/ch (typ)
Flash LED current: 150mA (typ)
All LED total maximum current: 200mA (typ)
Backlight LED current matching (I
LED
= 30mA)
:
±
3%
Flash LED current accuracy (I
LED
= 150mA)
:
±
5%
LDO (Low Dropout Regulator) output voltage
: 3.0V
±
2%
Packages: 20-pin QFN
WL-CSP (under development)
APPLICATIONS
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ORDERING INFORMATION
Device
SM8133BB
SM8133BW
Package
20-pin QFN
WL-CSP
Cellular phone
Digital still camera
PDA
Portable games
SEIKO NPC CORPORATION —1
SM8133B
PINOUT
(Top view)
QFN-20
SDA
SCK
RESETB
VOUT
LDOUT
WL-CSP (under development)
15 14 13 12 11
EN
DIN7
DIN6
DIN5
GND
16
17
18
19
20
1 2 3 4 5
10
9
8
7
6
VIN
C2P
C2M
C1M
C1P
D
C
B
A
5 4 3 2 1
PIN DESCRIPTION
Number
Name
QFN-20
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
WL-CSP
D1
C1
B1
B2
A2
A1
A3
B3
B4
A4
A5
B5
C5
C4
D5
D4
C3
D3
D2
C2
DIN4
DIN3
DIN2
DIN1
PGND
C1P
C1M
C2M
C2P
VIN
LDOUT
VOUT
RESETB
SCK
SDA
EN
DIN7
DIN6
DIN5
GND
O
O
O
O
–
–
–
–
–
–
O
O
I
I
I
I
O
O
O
–
LED drive current control output 4
(connect
to ground when not used)
LED drive current control output 3
(connect
to ground when not used)
LED drive current control output 2
(connect
to ground when not used)
LED drive current control output 1
(connect
to ground when not used)
Charge pump ground connection
Charge pump capacitor connection 1P
Charge pump capacitor connection 1M
Charge pump capacitor connection 2M
Charge pump capacitor connection 2P
Voltage supply
LDO output (leave open circuit when not used)
LED drive voltage output
Reset signal input (internal reset when RESETB is LOW)
Serial data clock input
Serial data input
Serial interface enable input
LED drive current control output 7
(connect
to ground when not used)
LED drive current control output 6
(connect
to ground when not used)
LED drive current control output 5
(connect
to ground when not used)
Ground
I/O
Description
DIN4
DIN3
DIN2
DIN1
PGND
SEIKO NPC CORPORATION —3
SM8133B
SPECIFICATIONS
Absolute Maximum Ratings
GND = PGND = 0V
Note. The device may suffer breakdown if any one of these parameter ratings is exceeded.
Parameter
Supply voltage range
Input voltage range
Output voltage range
VOUT output current
LDO output current
Power dissipation
Junction temperature
Storage temperature range
Symbol
V
IN
V
EN
, V
SCK
, V
SDA
V
DIN1 to 7
V
OUT
I
OUT
I
LDO
P
D
T
JMAX
T
stg
Rating
−0.3
to 5.5
–0.3 to V
IN
+ 0.3
–0.3 to V
IN
+ 0.3
5.5
500
200
1429 (Ta = 25°C)
*1
+125
−55
to +125
Unit
V
V
V
V
mA
mA
mW
°C
°C
*1. When mounted on a 34
×
40
×
1.6mm glass epoxy board, the power dissipation is related to the operating temperature
by the following equation.
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Maximum junction temperature: T
MAX
= 125°C
Operating temperature: Ta [°C]
Thermal resistance:
θ
J
= 70°C/W
Power dissipation [mW]
1600
1429
1200
1143
857
800
571
P
D
=
(T
MAX
−
Ta)
θ
J
400
0
25
35
45
55
65
75
85
Operating temperature [°C]
Recommended Operating Conditions
GND = PGND = 0V
Rating
Parameter
Pin
Symbol
V
IN1
Supply voltage range
VIN
V
IN2
V
IN3
Input voltage range
Ambient temperature range
EN, SCK,
SDA,
RESETB
−
V
ES
Ta
Conditions
min
×1.0
mode, I
OUT
= 0mA
×1.5
mode, I
OUT
= 80mA
×1.5
mode, I
OUT
= 200mA
Each logic-level pin
2.7
3.0
3.3
0
−30
typ
3.6
3.6
3.6
−
−
max
4.6
4.6
4.6
V
IN
+85
V
V
V
V
°C
Unit
SEIKO NPC CORPORATION —5
京公网安备 11010802033920号
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