PRODUCT DATASHEET
AAT3340
TM
ChargePump
High Efficiency 1x/1.5x Charge Pump
General Description
Features
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The AAT3340 is a low-noise, constant-frequency charge
pump DC/DC converter that uses a dual-mode load switch
(1x) and fractional (1.5x) conversion to maximize effi-
ciency for white LED applications. The AAT3340 is capable
of driving 4 white LEDs at a total of 80mA from a single
2.7V to 5.5V input. The current sinks may be operated
individually or in parallel while driving higher-current
LEDs. A low external parts count (two 1µF flying capacitors
and two small 1µF capacitors at VIN and VOUT) makes the
AAT3340 ideal for small battery-powered applications.
Dual-Mode (1x/1.5x) Charge Pump
Drives up to 4-Channel Backlight LEDs
32-Level Programmable Backlight Current (linear,
inverting)
Single-wire S2Cwire Control
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Built-in Thermal Protection
Automatic Soft Start
-40°C to +85°C Temperature Range
TSOPJW-12 and TDFN33-12 Packages
Analogic Tech’s Simple Serial Control (S2Cwire) digital
interface is used to enable, disable and set current to
one of 32 levels for the LEDs.
Applications
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Cellular and Smart Phones
Digital Still and Video Cameras
PDAs
Portable Devices
Portable Media Players
Other White LED Backlighting
The AAT3340 is equipped with built-in short-circuit and
over-temperature protection. The soft-start circuitry pre-
vents excessive inrush current at start-up and mode
transitions. The AAT3340 family is available in Pb-free,
space-saving TSOPJW and TDFN33 packages, and oper-
ates over the -40°C to +85°C ambient temperature
range.
Typical Application
C1+
C2+
C1
1µF
C1-
C2
1µF
C2-
VBATTERY
3.6V
IN
OUT
D1
D2
D3
D4
COUT
1µF
CIN
1µF
AAT3340
BL1
BL2
BL3
BL4
EN/SET
EN/SET
S2Cwire Serial Control
GND
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