The reference design features a 4.5V to 40V input range and 1A to 20A output. It uses a supercapacitor and buck-boost operation for efficient power management.
Supercapacitors, known for their high power density and rapid charge-discharge capabilities, are increasingly integral to terminal backup systems, offering a reliable alternative to traditional batteries. These devices excel in providing immediate energy during peak demands and feature a long lifespan with millions of charge cycles, minimal degradation, and excellent temperature stability. Ideal for environments where durability and quick response are crucial, supercapacitors enhance safety, reduce maintenance costs, and improve overall energy efficiency. Their ability to quickly stabilise power supplies without the risks associated with chemical batteries makes them critical in maintaining continuous operations in medical, industrial, and data-centred applications. The CN300-SCAPBACKPOCZ reference design from Renesas features a broad input voltage range from 4.5V to 40V and offers an output of 1A to 20A.
The design incorporates a supercapacitor for backup power, providing an alternative for systems traditionally relying on batteries and electric double-layer capacitors (EDLC) for backup. The ISL81401 40V bidirectional 4-switch synchronous buck-boost controller is designed to maximise the power extraction from a supercapacitor, which can operate at voltages as low as 0.3V. This controller facilitates a buck-boost operation using an electric double-layer capacitor (EDLC) for backup, ensuring optimal performance with the ISL81401. It offers a range of current options from 100mA to 70mA, providing versatility in application. The board provides a quick and cost-effective way to evaluate the performance in applications requiring a low-power, wide input voltage range. It is suited for point-of-load applications requiring both step-up and step-down voltage capabilities.
Key features of the system include a flexible design and bi-directional operation, which enhances usability in various configurations. It offers high light-load efficiency through pulse-skipping DEM operation. It is equipped with over-voltage protection (OVP), over-temperature protection (OTP), and under-voltage protection (UVP) to ensure safe operation. Additionally, the design includes a back bias from the output to improve overall efficiency and provides a convenient power connection setup. The board is the same test platform that Renesas application engineers and IC designers use to assess the performance of the ISL81401 QFN IC. This board offers a straightforward and comprehensive way to evaluate all the functions of both the IC and the board itself.
The ISL81401 and ISL81401A feature four independent control loops that manage input and output voltages and currents, enhancing the system’s precision. These devices integrate inherent peak current sensing at both ends and cycle-by-cycle current limits, ensuring high operational reliability. This function provides immediate current limitations under fast transient conditions at either end and in both directions. Additionally, two current monitoring pins at the input and output support the Constant Current limit and other system management functions, preventing runaway conditions in overloading or short-circuit scenarios.
Renesas has tested this reference design. It comes with a bill of materials (BOM), schematics, assembly drawing, printed circuit board (PCB) layout, and more. The company’s website has additional data about the reference design. To read more about this reference design, click here.
