AAT2860 Datasheet, PDF (1/23 Pages) Advanced Analogic Technologies – Backlight/Flash LED Driver and Multiple LDO Lighting Management Unit

PRODUCT DATASHEET
AAT2860
ChargePump^TM Backlight/Flash LED Driver and Multiple LDO Lighting Management Unit
General Description
The AAT2860-x is a highly integrated charge pump-based
lighting management unit (LMU) with three low dropout
(LDO) regulators optimized for single-cell lithium-ion/
polymer systems. The charge pump provides power for
all LED outputs; multiple backlight and flash LED configu-
rations are available. The backlight LED outputs can be
programmed up to 31mA each and the flash LED outputs
can be programmed up to 300mA each. An I²C compati-
ble serial digital interface is used to enable, disable, and
set the current to one of 32 levels for the backlight and
one of 16 levels for the flash. A programmable safety
timer and flash control input is included for easy flash
control. Backlight current matching is better than 3% for
uniform display brightness, and flash current matching is
better than 5% for uniform power dissipation.
The AAT2860-x offers three high-performance low-noise
MicroPower™ LDO linear regulators. The regulators are
enabled and their output voltages are set through the
I²C compatible serial interface. Each LDO can supply up
to 300mA load current and ground-pin current is only
80µA making the AAT2860-x ideal for battery-operated
applications.
The AAT2860-x is available in a Pb-free, space saving
TQFN34-24 package and operates over the -40°C to
+85°C ambient temperature range.
Features
• Input Voltage Range: 2.7V to 5.5V
• I²_{C Compatible Serial Interface}
• Tri-Mode Charge Pump
▪ Drives up to Seven LEDs (Backlight/Flash)
• Programmable Backlight Current Settings
▪ 32 Levels - 0.5mA to 31mA
• Programmable Flash Current
▪ 16 Levels – OFF to 300mA
• 1MHz Switching Frequency
• Automatic Soft-Start
• Three Low Dropout Regulators
▪ 300mA Output Current
▪ ^{150mV Dropout}
▪ Programmable Output from 1.5V to 3.0V
▪ Output Auto-Discharge for Fast Shutdown
• Built-In Thermal Protection
• -40°C to +85°C Temperature Range
• TQFN34-24 Package
Applications
• Camera Enabled Mobile Devices
• Digital Still Cameras
• Multimedia Mobile Phones
Typical Application
V_BAT
3.6V
C_IN
4.7µF
C_IN
4.7µF
LED Select
Flash Level Select
I²C Serial ^SDA
Interface
SCL
LDO Select
C1
C2
1µF
1µF
C1+ C1- C2+ C2-
IN
OUT
AAT2860-x
IN
LED_SEL
FL_LVL
SDA
SCL
BL1
BL2
BL3
BL4
BL5
BL6/FL1
BL7/FL2
LDOA
LDO_SEL LDOB
AGND
LDOC
PGND
WLEDs
OSRAM LW M673
or equivalent
V_OUT
C_OUT
2.2µF
Flash LEDs
Lumiled LXCL-PWF1
or equivalent
VLDOC
at 300mA
C_LDOC
2.2µF
V_LDOB
at 300mA
CLDOB
2.2µF
VLDOA
at 300mA
C_LDOA
2.2µF
2860.2008.05.1.0
www.analogictech.com
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