AnalogicTech Announces Dual-output Step-down Converter For 12V Adapter Applications
Advanced Analogic Technologies, Inc. (AnalogicTech™) announced the AAT2688, an integrated synchronous step-down converter and low-dropout (LDO) regulator for 12V adapter systems. The company claims that, by leveraging the unique advantages of its proprietary high voltage Modular BCD process, the new device helps save power and reduces thermal dissipation by delivering efficiency levels up to 90%.
"Driven by cost considerations, many popular 12V consumer electronics systems such as set-top boxes, WLAN systems and DSL and cable modems, are forced to accept lower than optimal levels of power efficiency," says CJ Zhang, Product Line Vice President at AnalogicTech. "By integrating a synchronous step-down converter with a wide input range and an LDO optimized for low noise and low current, the AAT2688 allows designers to have the best of both worlds - power efficiency up to 90 percent and a dual-output power management solution in a compact, space-saving footprint."
Channel one on the dual output AAT2688 is a buck converter which operates off a wide 6 to 24V input voltage making the device ideal for low-cost 12V adapter applications. The buck converter delivers a 4.5A output and converts 12 to 3.3V at a 4.5A load with up to 90% efficiency.
A high 490 kHz fixed switching frequency supports the use of small external L/C filtering components. Voltage mode control optimizes operation across the entire output voltage and load range. The buck converter offers accuracy ± 1.5%. The second channel on the AAT2688 provides a low input voltage LDO. This function operates off a 2.7 to 5.5V input voltage and delivers up to 600mA. The LDO is said to combine low output noise and low quiescent current with excellent transient response.
To maximize designers’ options, the AAT2688 provides independent input and enable pins for each function. To ensure device integrity, the new device also features internal soft start, over-current and over-temperature protection circuits.
The AAT2688 is qualified across the -40 to +85°C temperature range. It comes in a 4 x 5-mm, 24-pin TQFN package. The IC sells for $1.25 in 1K quantities.
