General Description
The AAT3132/32A is a low noise, constant frequency charge pump DC/DC converter that uses fractional (1.5X) conversion to maximize efficiency for white LED applications. The device can be used to produce current levels up to 20mA in three of its outputs and up to 25 or 30mA in one of its 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) makes the AAT3132/32A ideally suited for small battery-powered applications.
FEATUREs
• VIN Range: 2.7V to 5.5V
• <1.0µA of Shutdown Current
• 1MHz Switching Frequency
• White LED Backlighting
• Fully Independent Display Lighting
• Drives Low-VF and High-VF Type LEDs
• Up to Three 20mA Outputs
• Single 25mA Output (AAT3132-1)
• Single 30mA Output (AAT3132/32A)
• Multi-Position Logarithmic Scale with Digital Control
• Low Noise Constant Frequency Operation
• Regulated Output Current
• Automatic Soft Start
• No Inductors
• -40°C to +85°C Temperature Range
• 12-Pin TSOPJW Package
APPLICATIONs
• Color (RGB) Lighting
• Programmable Current Source
• White LED Backlighting
• White Photo Flash for Digital Still Cameras