Specifications- Input Supply Voltage Range: 2.7V to 5.5V
- Tri-Mode (1X/1.5X/2X) Charge Pump
- Maximizes Efficiency
- 1MHz Constant Switching Frequency
- No Inductors, Low Noise Operation
- Drives Four Channels of LEDs up to 40mA/ Channel
- User-Programmable LED Current using and external resistor
- Excellent LED Channel-to-Channel Current Matching
- Digitally Programmable LED Current with Single-Wire S2Cwire Interface
- 16 Current Levels From 40mA to 50A
- Low IQ (50A) for Low Current Mode Operation
- True Load Disconnect in Shutdown; IQ < 1A
- Built-In Thermal Protection
- Built-In Auto-Disable for Open LED Circuit
- Automatic Soft-Start Minimizes Inrush Startup Current
- 2.85x3x1mm TSOPJW-14 Package
Descriptionspan id="lblDescription">
The AAT3159 is a low noise, constant frequency charge pump DC/DC converter that uses a tri-mode load switch (1X), fractional (1.5X), and doubling (2X) conversion to maximize efficiency for white LED applications. The device is capable of driving up to four channels of LEDs at up to 40mA per channel from a 2.7V to 5.5V input supply voltage. The current sinks may be operated individually or in parallel for driving higher-current LEDs. A low external parts count (two 1F flying capacitors [C1 and C2] and two small 1F capacitors [CIN and COUT]) makes this part ideally suited for small battery-powered applications.
AnalogicTech patented single-wire Simple Serial Control™ (S2Cwire™) serial digital interface is used to enable, disable, and set the current for each LED with 16 levels from a maximum of 40mA down to 50A. The maximum current level is programmed via an external resistor. To save power, low-current mode supply current will be as low as 50A.
Each output of the AAT3159 is equipped with built- in protection for VOUT short-circuit operation and auto-disable functionality for LED open-circuit conditions. Built-in soft-start circuitry prevents excessive inrush current during start-up. A low-current shutdown feature disconnects the load from IN and reduces quiescent current to less than 1A.
The AAT3159 is available in a Pb-free, space-saving 2.85x3x1mm TSOPJW-14 package.
AAT3159 Data Sheet
