Pair of DC/DC controllers have extra voltage margin
Two 80V DC/DC controllers from Renesas provide the extra voltage margin required for 48V telecomms, data centre and industrial applications. The ISL81801 bi-directional, four switch, synchronous buck-boost controller and the ISL81802 dual synchronous buck controller are available now.
They are supplied in 5.0 x 5.0mm, 32-lead QFN packages and 38-lead, 4.4 x 9.7mm heat sink, thin shrink, small outline packages (HTSSOP).
The ISL81801 buck-boost controller enables bi-directional current flow (forward or reverse) using constant voltage and constant current regulation. This allows a battery or supercapacitor to be charged and discharged using a single controller and power path. It is claimed to combine the industry’s highest 80V buck-boost switching frequency (600kHz) and smallest package (5.0 x 5.0mm) for compact, high-density power design. The wide range (4.5V to 80V) is particularly suitable for common applications, including 48V motor drives, telecomms, industrial battery back up systems and solar power.
The ISL81802 is a single-chip, 80V dual-phase synchronous buck controller with integrated drivers. It is believed to be the industry’s only 80V buck controller capable of 1MHz switching frequency, enabling the use of small power supply inductors to improve power density. For higher power applications, multiple ISL81802s can be paralleled and interleaved with best-in-class transient response.
The ISL81802 can generate either two independent outputs, or a single high-current output, allowing creative power supply engineers tremendous flexibility and IP re-use across platforms. The capability to supply either a constant output voltage or a constant current makes a range of end-user applications possible, from LED drive to powering blowers to maximise airflow in dense data centre systems.
According to “Philip Chesley, vice president of the Industrial and Communications business division at Renesas: “Leveraging Renesas’ proprietary modulation scheme and algorithms allows the highly integrated ISL81801 and ISL81802 to achieve the highest reliability performance, and the ability to react quickly to transient loads with a minimum number of BoM components.”
Both DC/DC controllers have multi-layer protection for over-voltage, under-voltage lock-out, over-temperature, average and peak current limit on both outputs, and shoot-through protection for MOSFET drivers
