SM8133B_06 Datasheet, PDF (1/23 Pages) Nippon Precision Circuits Inc – White LED Driver IC

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
I Noise reduction due to charge pump boost circuit
I Automatic charge pump switching to conserve
power
I Drives 1 to 6 backlight white LED
(30mA/ch at maximum setting)
I Drives a flash white LED
(150mA at maximum setting)
I Backlight and flash white LED brightness
adjustment
I Group settings for 2-group backlight lighting
control
I 3-wire serial input interface for all setting and
control
I 3.0V output LDO circuit built-in
I Shutdown function by RESETB pin
I Soft start circuit built-in
I Thermal protection circuit built-in
I 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
I Quiescent current
• LDO only: 0.3mA (typ)
• Not -switching (×1.0 mode): 0.5mA (typ)
• Switching (×1.5 mode): 2.5mA (typ)
I Standby current: 0.01µA (typ)
I Operating frequency: 750kHz (typ)
I Backlight LED current: 30mA/ch (typ)
I Flash LED current: 150mA (typ)
I All LED total maximum current: 200mA (typ)
I Backlight LED current matching (I_LED = 30mA)
: ± 3%
I Flash LED current accuracy (I_LED = 150mA)
: ± 5%
I LDO (Low Dropout Regulator) output voltage
: 3.0V ± 2%
I Packages: 20-pin QFN
WL-CSP (under development)
APPLICATIONS
I Cellular phone
I Digital still camera
I PDA
I Portable games
ORDERING INFORMATION
Device
SM8133BB
SM8133BW
Package
20-pin QFN
WL-CSP
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