Integrated DC/DC converters with high-efficiency design


Murata’s UltraBK family of DC/DC converter uses a multi-patented design that significantly reduces the footprint and height of power-conversion circuitry.

The UltraBK converters are aimed at space-constrained applications such as IT and network infrastructure equipment. In addition to unprecedented space savings, they deliver high energy efficiency, high reliability, outstanding low-noise performance, and fast transient response.

The converters achieve their extremely low height and compact footprint using an innovative two-stage design. This design combines a switched-capacitor charge pump followed by a smaller buck or boost converter with lower-voltage power MOSFETs and reduced output inductance compared to conventional designs. The capacitor network provides almost lossless conversion of the input voltage at any ratio, enabling overall operating efficiency as high as 90.5%. The output inductor is approximately 10 times smaller than for a comparable conventional circuit, allowing the entire converter to fit in a 10.5 mm x 9.0 mm LGA package only 2.1 mm high. Moreover, electromagnetic emission (EMI) is typically 20 dB lower.

“Conventional power converters can occupy 30-50% of circuit-board real estate and typically require large, tall inductors that pose layout challenges and can interfere with cooling airflow,” said Shuji Mikami, Power Modules Division, Low Power Products Department, Murata. “Our UltraBK™ family changes everything for designers, simplifying board design and thermal management while also raising power density and delivering excellent energy efficiency, transient performance, and low noise emission.”

Murata is launching the UltraBK™ family by introducing four buck converters that provide a choice of 4 A and 6 A output ratings and the option of a built-in I2C port to allow digital configuration and control. The converters have a wide input voltage range of 6.0 V to 14.4 V, with programmable output voltage from 0.7 V to 1.8 V.

The 4A MYTNA1R84RELA2RA and 6A MYTNA1R86RELA2RA, and similar MYTNC1R84RELA2RA and MYTNC1R86RELA2RA with I2C control, are now available from Murata’s distributors.