Alpha and Omega Semiconductor Ltd. (AOS) recently introduced dc-dc synchronous buck regulators, the AOZ6682CI and the AOZ6683CI. The new devices are both available in a thin, thermally enhanced TSOT23-6 package and deliver 2- and 3-A output current, respectively. According to AOS, they offer high efficiency over the full load range, allowing for greener power conversion for a variety of consumer electronics applications such as LCD TVs, set-top boxes, high-definition Blu-ray disc players, and networking terminals.
The new devices incorporate a low-resistance synchronous buck power stage that enables up to 95% efficiency. Combined with the thermally enhanced package, they achieve 10°C cooler operation at full load compared with similar competing devices, says the company. Under heavy load conditions, the devices operate in a fixed-frequency continuous-conduction mode (CCM). At light loads or in standby mode, the devices employ a proprietary pulse-energy-mode (PEM) control scheme. This control scheme and a low quiescent current of 200 µA allows the buck-converter design to achieve efficiencies of 89% at light loads.
“Modern consumer equipment must achieve less than 0.5 W in standby power consumption and this is a tough problem for system designers to solve,” said Kenny Hu, power IC marketing manager at AOS. “The newest 2- and 3-A additions to the EZBuck family simplify this task, offering up to 6% improved efficiency compared with competing devices, thanks to low quiescent current and a proprietary power-saving light-load control scheme.”
Technical Highlights
