AAT3103 Datasheet, PDF (1/17 Pages) Advanced Analog Technology, Inc. – 3-Channel Charge-Pump LED Driver

ChargePump^TM
General Description
The AAT3103 is a constant frequency charge-pump based
current-source white LED driver capable of driving one to
three LEDs up to 30mA, each. The charge pumps auto-
matically switch between 1x mode and 2x mode to main-
tain the highest efficiency and optimal LED current accu-
racy and matching. A low external parts count (one 1μF
flying capacitor, two small 1μF capacitors at IN and OUT
and one current setting resistor) makes the AAT3103 ide-
ally suited for small battery-powered applications.
The AAT3103-1/-2 uses AnalogicTech's Simple Serial
Control™ (S²Cwire™) interface to enable, disable, and
program the LED driving current. The AAT3103-4 employs
a Pulse Width Modulation (PWM) signal with up to 50kHz
frequency, 10% to 100% duty cycle to program the LED
current. A low-current shutdown feature disconnects the
load from IN and reduces quiescent current to less than
1μA. Built-in soft-start circuitry prevents excessive inrush
current during start-up. Integrated short circuit and ther-
mal protection circuitry protects the device from damage.
The AAT3103 is available in a 2x2.1mm thermally
enhanced Pb-free 10-lead SC70JW-10 package.
PRODUCT DATASHEET
AAT3103
3-Channel Charge-Pump LED Driver
Features
• Source WLED Driver, up to 3 LEDs at up to 30mA, each
• Automatic Switching Between 1x and 2x Modes
• 900KHz Switching Frequency
• Linear LED Output Current Control
▪ Single-wire, S²Cwire Interface
AAT3103-1: 16-step
AAT3103-2: 8-step
▪ ON/OFF or PWM Interface
AAT3103-4
• ±10% LED Output Current Accuracy
• ±3% LED Output Current Matching
• Low-current Shutdown Mode
• Built-in Short Circuit and Thermal Protection
• Automatic Soft-start
• 2x2.1mm SC70JW-10 Package
Applications
• Cordless Phone Handsets
• Mobile Phone Handsets
• MP3 and PMP Players
• Digital Cameras
Typical Application
Input Voltage
2.7V to 5.5V
CIN
1μF
CP
1μF
EN /SET
S²Cwire
Interface
RSET
14.3kΩ
IN
C+
OUT
AAT3103-1
C-
EN/SET
D1
D2
RSET
D3
AGND
COUT
1μF
WLEDs
OSRAM LW M 678
or equivalent
3103.2008.03.1.0
www.analogictech.com
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