Specifications- VIN Range: 2.7V to 5.5V
- Dual Channel Output
- Up to 1.5A Regulated Output Current (750mA per channel)
- Up to 85% Efficiency with Small Inductor (1H)
- 2 MHz Switching Frequency
- Separate Flash Enable
- User-Programmable Safety Timer
- Single Resistor Sets Flash and Movie Mode Current
- Two Wire, I2C Compliant Serial Interface
- Fast, 400kHz Serial Transfer Rate
- 16 Level Movie-mode Current
- Flash/Movie-mode
- Current Output Channel Control
- Safety Timer
- True Load Disconnect
- Input Current Limit
- Over-Voltage (Open LED, Open Circuit), Short Circuit, and Over-Temperature Protection
- Shutdown Current < 1.0A
- 14-pin TDFN 3x3 mm Package
- -40C to +85C Temperature Range
Descriptionspan id="lblDescription">
The AAT1272 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 AAT1272 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 AAT1272 ideally suited for small battery-powered applications.
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 AAT1272 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; the ratio of Flash to Movie-mode current is set at approximately 7.3:1. One or two LEDs can be connected to the AAT1272; in the case of two LEDs the output current is matched between each diode.
The AAT1272 contains a thermal management system to protect the device in the event of an output short-circuit condition. Built-in circuitry prevents excessive inrush current during start-up. The shutdown feature reduces quiescent current to less than 1.0A.
The AAT1272 is available in a Pb-free, thermally-enhanced 14-pin 3x3mm TDFN package.
AAT1272 Data Sheet
