AAT3140 High Efficiency 1X/1.5X Fractional Charge Pump for White LED Applications
The AAT3140 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 AAT3140 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 AAT3140 ideally suited for small battery-powered applications. Skyworks' proprietary AS2Cwire™ (Advanced Simple Serial Control™) serial digital interface is used to enable, disable, configure, and program the operation of the AAT3140. Using the AS2Cwire interface, the movie-mode current level for the 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 AAT3140 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 Movie-mode current is set at approximately 7.3:1. The AAT3140 can drive one high current LED. The AAT3140 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 1.0μA.
技术特性
- VIN Range: 2.7V to 5.5V
- Tri-Mode 1X, 1.5X, and 2X Charge Pump for Maximum Efficiency and VF Coverage
- Drives Low-VF and High-VF Type LEDs
- Up to Four 30mA Outputs
- 32-Position Logarithmic Scale with Digital Control
- Low Noise Constant Frequency Operation
- 1MHz Switching Frequency
- AutoBias Technology
- Small Application Circuit
- Regulated Output Current
- Automatic Soft Start
- No Inductors
- Q < 1μA in Shutdown
- 12-Pin TSOPJW Package
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应用领域 APPLICATION
- Color (RGB) Lighting
- Programmable Current Source
- White LED Backlighting
- White Photo Flash for DSCs
订购信息 Ordering Information
AAT3140 典型应用
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