AAT3121 Datasheet | Skyworks Solutions

Description The AAT3121 is a low noise, constant frequency charge pump DC/DC converter that uses fractional (1.5X) conversion to increase efficiency in white LED applications. With input voltages ranging from 2.7V to 5.5V, the device can produce an output current of up to 120m A. A low external parts count (two 1µF flying capacitors and two small bypass capacitors at VIN and OUT) makes the AAT3121 ideally suited for small battery-powered applications. Skyworks' Simple Serial Control™ (S2Cwire™) interface is used to enable, disable, and set the LED drive current with a 32-level logarithmic scale LED brightness control. The AAT3121 has a thermal management system to protect the device in the event of a short-circuit condition on any of the output pins. Built-in soft-start circuitry prevents excessive inrush current during start-up. High switching frequency enables the use of small external capacitors. A low shutdown current feature disconnects the load from VIN and reduces quiescent current to less than 1µA. The AAT3121 provides a single current source output that can be used to drive up to six LEDs at 20m A each. The AAT3121 is available in a Pb-free TSOPJW-12 package and is rated over the -40°C to +85°C temperature range. Features - VIN Range: 2.7V to 5.5V - <1µA of Shutdown - Only Four External ponents - Programmable LED Brightness - Low Noise Constant Frequency Operation - 33% Less Input Current Than Doubler Charge Pump - Small Application Circuit - Regulated Output Current - Automatic Soft Start - No Inductors - TSOPJW-12 Package - -40°C to +85°C Temperature Range Applications - Programmable Current Source - White LED Backlighting Typical Application VBATTERY COUT 1µF 1µF EN/SET C1+ VOUT C1- C2+ C2- EN/SET C1 1µF C2...