
Analog Technology Inc
General Description
The AAT3134 is a low noise, constant frequency charge pump DC/DC converter that uses a dual mode load switch (1X) and fractional (1.5X) conversion to maximize efficiency for white LED applications. The device can be used to produce current levels up to 20mA in each of its six outputs to drive LEDs from a 2.7V to 5.5V input. Outputs may be operated individually or paralleled for driving higher-current LEDs. A low external parts count (two 1µF flying capacitors and two small 1µF capacitors at VIN and OUT) make the AAT3134 ideally suited for small battery-powered applications
FEATUREs
• VIN Range: 2.7V to 5.5V
• <1.0µA of Shutdown
• 1MHz Switching Frequency
• Fully Independent Display Lighting
• Dual Mode 1X and 1.5X Charge Pump for Maximum Efficiency
• Drives Low-VF and High-VF Type LEDs
• Up to Six 20mA Outputs
• Multi-Position Brightness Scale with Digital Control
• Low Noise Constant Frequency Operation
• Small Application Circuit
• Regulated Output Current
• Automatic Soft Start
• No Inductors
• 16-Pin QFN44 Package
• -40°C to +85°C Temperature Range
APPLICATIONs
• Color (RGB) Lighting
• Programmable Current Source
• White LED Backlighting
• White LED Photo Flash for Digital Still Cameras