AAT1271A

The AAT1271A is a high-efficiency, high-current boost converter capable of 1.5A typical output current. It is an ideal power solution for LED photo flash applications in all single cell Li-ion powered products.

The AAT1271A 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 AAT1271A ideally suited for small battery-powered applications.

AnalogicTech's proprietary AS2Cwire™ (Advanced Simple Serial Control™) serial digital interface is used to enable, disable, configure, and program the operation of the AAT1271A. Using the AS2Cwire interface, the moviemode current level for each LED, the safety timer delay, and the flash-to-movie-mode current ratio can be programmed to one of 16 levels. In addition, the single-wire serial protocol sets output channel control. The AAT1271A also includes a separate Flash Enable input to initiate both the flash operation and the default timer which can be used either to terminate a flash event at the end of a user-programmed delay or as a safety feature. Also included is a Flash Inhibit pin which reduces the flash current to movie-mode levels during high battery demand.

The maximum flash and movie-mode current is set by one external resistor where the ratio of Flash to Moviemode current is set at approximately 7.3:1. One or two LEDs can be connected to the AAT1271A, where in the case of two LEDs the output current is matched between each diode.

The AAT1271A contains a thermal management system to protect the device in the event of an output shortcircuit condition. Built-in circuitry prevents excessive inrush current during start-up. The shutdown feature reduces quiescent current to less than 1.0A.

The AAT1271A is available in a Pb-free, thermallyenhanced 14-pin 3x3mm TDFN package.