Features: • VIN Range: 2.7V to 5.5V
• Dual Charge Pump:
- Flash: Charge Pump Doubler
- Backlight: Tri-Mode Charge Pump
• Backlight Charge Pump:
- Programmable Current With Single GPIO
- 16 Current Steps
- 15/20/30mA Max Current
- Four Low Current Settings
- Individual Main/Sub-Group Control
- Low IQ (50A) for Low-Current Mode
- Drives Six Channels of LEDs
• Flash Charge Pump:
- Regulated VOUT_FL 4.5/5.0 Volts
- Up to 300mA of Current for Flash
• 1MHz Constant Switching Frequency
• Independent Backlight/Flash Control
• Built-In Thermal Protection
• Built-In Auto-Disable for Open Circuit
• Automatic Soft Start
• IQ <1A in Shutdown
• Available in QFN44-24 PackageApplication• Color (RGB) Lighting
• Programmable Current Sink
• White LED Backlighting
• White Photo Flash for Digital Still CamerasPinout
Specifications
| Symbol |
Description |
Value |
Units |
| VIN |
Input Voltage |
-0.3 to 6 |
V |
| VEN/SET |
EN/SET to GND Voltage |
-0.3 to VIN + 0.3 |
V |
| TJ |
Operating Junction Temperature Range |
-40 to 150 |
|
| TLEAD |
Maximum Soldering Temperature (at leads, 10 sec) |
300 |
|
DescriptionThe AAT2803 is a dual charge pump designed to support both white LED backlight and flash applications for systems operating with lithium-ion/polymer batteries. The backlight charge pump is capable of driving up to six LEDs at a total of 180mA. The current sinks may be operated in group or in parallel for driving higher current LEDs. To maximize power efficiency, the charge pump operates in 1X, 1.5X, or 2X mode, where the mode of operation is automatically selected by comparing the forward voltage of each LED with the input voltage. AnalogicTech's AS2Cwire™ (Advanced Simple Serial Control™) serial digital input is used to enable, disable, and set current for each LED with a 16-level logarithmic scale plus four lowcurrent settings down to 50A for optimized efficiency, with a low housekeeping current of only 50A.
The flash charge pump AAT2803 is a charge pump doubler with a regulated output voltage. It is designed to deliver 120mA of continuous current and up to 300mA of pulsed current. It has an independent enable pin for improved power savings.
The AAT2803 is equipped with built-in protection, short-circuit, and auto-disable for load short-circuit condition. Built-in soft-start circuitry prevents excessive inrush current during start-up. A low-current shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1A.
The AAT2803 is available in a Pb-free, space-saving, thermally enhanced 24-pin 4x4mm QFN package and is rated over the -40°C to +85°C temperature range.
AAT2803 Data Sheet
