Fixed-frequency Synchronous Buck Regulators with 30 ns minimum On-Time suitable for noise-sensitive applications
Alpha and Omega Semiconductor introduced AOZ676xDI series of high switching frequency and simple-to-use synchronous buck regulators. AOZ6762DI and AOZ6763DI are capable of delivering 2 A and 3 A, respectively, and up to 15 W output power. The new devices offer a low on-resistance power stage and are packaged in a 3 mm × 3 mm DFN 8-lead package with an exposed thermal pad, allowing cooler power conversion for a variety of consumer and networking equipment such as wireless AP/routers, set-top boxes, cable modems, audio equipment, and LCD TVs.
The power stage comprised of two power MOSFETs optimized for efficient synchronous switching to minimize both switching and conduction losses. The new devices can achieve > 90% efficiency at full load operation. When operating in low output current conditions, the devices run in a proprietary pulse energy mode (PEM) to achieve high efficiency by reducing switching loss. Under this mode, the regulators can still maintain up to 86% efficiency at 10 mA load operation. This feature enables system designers to achieve the low standby power required to meet the “One Watt Initiative.”
The high switching frequency of AOZ6762 and AOZ6763 provides some key benefits in a buck regulator
- Enables the use of smaller external components, such as inductors and capacitors, reducing PCB footprint and component costs.
- Better transient response while maintaining fixed frequency switching.
- Reduce the side-band interference in wireless applications.
High switching frequency combined with low minimum controllable on-time makes AOZ6763 and AOZ6762 unique, enabling low output voltages from a 12 V bus making the device a suitable power converter for next-generation SoCs, FPGAs, and ASICs using deep sub-micron processes. External compensation makes it easy for the user to trade off transient response and output ripple requirements with various output filters.
|Maximum Current||2 A||3 A|
|Input Range||4.5 V to 18 V|
|Light Load Efficiency at 10 mA||86%|
|Minimum On-Time||30 ns|
|Minimum Output Voltage||0.6 V|
|Package||Thermal Enhanced DFN3x3-8L|
|Thermal Rise at 15 W Output||57 °C|
Pricing and Availability
The AOZ6762DI and the AOZ6763DI are immediately available in production quantities with a lead-time of 12 weeks. The unit price for 1,000 pieces is $0.42 for the AOZ6762DI and $0.52 for the AOZ6763DI.
|Efficiency vs. load current for AOZ6762DI at 12 V input voltage.|