Only For Training And Service Purposes - LG KS660 Service Manual

3. TECHNICAL BRIEF
The AAT1270 is a high-efficiency, high-current boost converter capable of 1A maximum output current. It
is an ideal power solution for LED photo flash applications in all single cell Lithium-ion / polymer battery
operated products.
The AAT1270 maintains output current regulation by switching the internal high-side and low-side switch
transistors. The transistor switches are pulse-width modulated at a fixed frequency of 2MHz. The high
switching frequency allows the use of a small inductor and output capacitor, making the AAT1270 ideally
suited for small battery-powered applications.
AnalogicTech's proprietary S2Cwire™ (Simple Serial Control™) serial digital interface is used to enable,
disable and set the movie mode current level for the flash LEDs to one of 16 levels. The AAT1270 also
includes a separate Flash Enable input to initiate both flash/strobe operation and the default timer, which
can be used to terminate a flash event after a user-programmed delay
or as a safety feature. A Flash Inhibit pin is also included which reduces flash current to movie mode
level during high battery demand.
The maximum flash and movie mode current is set by one external resistor; the ratio between flash and
movie mode current is set at approximately 7.3:1. One or two LEDs can be connected to the AAT1270;
when two LEDs are used, the output current is matched between each diode.
The AAT1270 contains over-voltage protection and a thermal management system to protect the device
in the event of an output open-circuit and short-circuit condition respectively. Built-in circuitry prevents
excessive inrush current during start-up. The shutdown feature reduces quiescent current to less than
1.0μA.
The AAT1270 is available in a Pb-free, thermally-enhanced 14-pin 3x3mm STDFN package.
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Only for training and service purposes