AAT1282

DATA SHEET AAT1282 2A Driver for High Intensity LED Camera Flash General Description The AAT1282 is a high-efficiency, high-current step-up converter capable of 2A maximum output current. It is an ideal power solution for LED photo flash applications in all single cell Li-ion powered products. The AAT1282 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 AAT1282 ideally suited for small battery-powered applications. A high-capacity Super Capacitor on the secondary side of the step-up converter provides the high-peak flash LED current, thereby reducing the peak current demand from the Li-ion battery. To achieve this, the step-up converter features a fixed, input current limiter. An industry-standard I2C serial digital input is used to enable, disable and set the movie-mode current for each flash LED with up to 16 movie-mode settings. The AAT1282 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. The maximum flash and movie-mode current is set by one external resistor where the ratio between Flash to Movie-mode current is set at approximately 7.3:1. One or two LEDs can be connected to t...