New Industry Products

Efficient, Reliable and Easy-to-Use 3-A Synchronous Buck Regulators

June 09, 2014 by Jeff Shepard

Intersil Corporation today announced the ISL85003 and ISL85003A 3-A synchronous buck regulators with integrated high-side and low-side MOSFETs. The new buck regulators support an input voltage range of 4.5V to 18V while delivering an efficient and continuous 3A current for the latest generation of FPGAs from leading manufacturers for high-end server, network communication and industrial process control applications. These buck regulators are claimed to be the most efficient regulators of their kind, reducing power loss, eliminating the need for fans or other cooling systems, improving reliability and extending the life of end products. The ISL85003/3A buck regulators are designed to deliver a very low resistance in a triode region RDS(on) with an optimized current mode controller to further improve efficiency and reduce die temperatures, keeping complex systems cooler and preventing product failures.

Many 12V infrastructure and industrial applications need a buck regulator solution to step the system voltage down to 3.3V and lower while delivering a continuous 3A current. These applications require a high level of reliability and low power loss to extend product life and reduce risk of system failure. Existing 3A solutions have failed to meet the needs of these applications because they frequently hit their temperature limits, which reduces power management efficiency and product reliability.

Intersil specifically designed the new 3A synchronous buck regulators to operate at and enable the highest efficiency, making systems more robust with consistent and reliable performance. Based on a proprietary high-performance power FET, the ISL85003/3A's high-side FET runs at 65mΩ and the low-side RDS(on) runs at 45mΩ. This makes them the lowest RDS(ON) buck regulator solutions in the market place with up to 95 percent efficiency. Greater efficiency translates to lower die temperatures, keeping the system cooler and reducing reliance on fans or other outside cooling systems. The highly efficient FETs also enable the ISL85003/3A buck regulators to work in applications that do not have expensive cooling systems.

The ISL85003/3A buck regulators offer a light load mode that allows systems to go into sleep mode when power requirements drop, effectively consuming less power. Many applications are reducing overall power consumption due to governmental regulations worldwide. As a result, companies are redesigning their products to meet these aggressive new requirements. In particular, the industrial market has seen a wave of new power efficient products that utilize energy saving design techniques such as sleep mode.

These products range from high-end server and programmable logic controllers (PLCs) to smart home and smart factory applications that require an extended battery charge. In many cases, the microcontroller or FPGAs are put into sleep mode during down time. For applications in which the load can vary from full operation to low power state, having a light load mode feature improves the overall system efficiency. In applications that do not require light load mode, designers can easily disable the feature, reducing the switching frequencies and simplifying design.

Unlike competing solutions, efficiency doesn't come at the cost of switching frequency with Intersil's new buck regulators. The ISL85003 buck regulator's switching frequency runs at 500KHz or can be synchronized to a clock up to 2MHz. This high switching frequency enables smaller inductors for the design and lower ripple, further improving efficiency and ease of design.

The combination of Intersil's ISL9444 3-output synchronous buck controller in conjunction with the ISL85003 3A synchronous buck regulator gives system level designers the flexibility and support needed to effectively deploy the latest generation multi-controller core SoCs and FPGAs from leading manufacturers. These highly flexible platforms can be found in a variety of industrial applications, such as 6 axis robotic controllers, grid tied PV inverters and medical imaging systems.

"From process technology to circuit design, Intersil is investing in new ways to improve power efficiency in our customers' most rigorous applications," said Mark Downing, senior vice president of infrastructure and industrial power products at Intersil. "The ISL85003/3A synchronous buck regulators are the most efficient solutions in their class, giving designers a new level of efficiency, flexibility and ease of design."

The ISL85003 and ISL85003A synchronous buck regulators are available now, priced at $1.35 (USD) each in 1,000-piece quantities. The ISL85003EVAL2Z and ISL85003EVALA2Z evaluation boards are available for $75 (USD) each. In addition, a low-cost demo board ISL85003DEMO1Z can be purchased for $20 (USD) each.