ROHM Semiconductor – New DC-DC regulator IC supplies board-level components directly from 48V power rail


ROHM Semiconductor has introduced a DC-DC regulator IC which can step down the input from a 48V power rail directly to the low voltage required by board-level components, without the need for an intermediate power stage, while operating at a high switching frequency of 2MHz.

This enables designers to develop power circuits that use fewer and smaller components, occupy less board space and have a lower bill-of-materials cost.

The BD9V101MUF-LB regulator benefits from the development by ROHM of ultra-high speed Nano Pulse Control® technology. This technology combines advanced techniques for circuit design and layout with new device fabrication processes. With it, ROHM has shortened the on-time in its device’s PWM control scheme to intervals as short as 9ns, enabling the BD9V101MUF-LB to achieve a very wide input:output voltage ratio of 24:1 at high switching frequencies.

The development of Nano Pulse Control technology comes in response to the increasing use of a 48V power distribution bus in mild- and full-hybrid vehicles, as well as in industrial equipment and in telecoms power supplies.

Typical power-system architectures involve an intermediate conversion stage, stepping the 48V bus supply down to 12V with a further conversion to the


  • Input-voltage range: 16V to 60V
  • Output-voltage range: 0.8V to 5.5V
  • Output-voltage accuracy: ±2%
  • 1A maximum output current
  • Operating-temperature range: -40°C to 125°C


  • Industrial equipment
  • Telecoms equipment
  • Base transmitter stations
  • Automotive systems