Buck-Boost DC-DC converter with 97 percent efficiency for battery designs

New Products | August 27, 2019

By Nick Flaherty

Batteries / Power Supplies

Rohm has launched a buck-boost DC-DC converter that integrates a MOSFET with a patented buck-boost control scheme to provide an efficiency of 97 percent.

The BD83070GWL was developed to be the best-in-class product for low power eco-friendly devices used in compact battery-driven applications. The built-in low-DS(on) MOSFET and low control current circuitry achieve an industry-leading power conversion efficiency of 97 percent during operation at 200mA load current (and 90 percent at low and high loads).

The DC-DC converter provides a 3.3 V or 2.5 V output from a single-cell Li-ion battery or other input between 2.0 V and 5.5 V with an output up to 1 A output. It seamlessly changes between buck and boost operations depending on the input voltage using a patented pulse width modulation (PWM) algorithm. While in PWM operation, the internal FETs switch at a fixed frequency of 1.5 MHz, and automatically changes over control system to hysteresis pulse frequency modulation (PFM) to suppress switching loss and current consumption during light load.

The high efficiency and quiescent current of 2.8µA enables longer operating time in compact battery-driven devices, prolonging battery life by as much as 1.53 times when compared to other conventional products during standby (100µA load current). An evaluation board integrating this converter is also available.

The BD83070GWL is packaged in a 1.2mmx1.6mm WLCSP and is built on a 0.13µm power process and joins the high efficiency ultra-low-power BU33UV7NUX boost converter and BD70522GUL buck converter that allow users to significantly extend the operating time of battery-powered applications. The target applications are IoT sensors driven by coin batteries, as well as smartphones and toys.

Samples are available now with volume in October. The BD83070GWL-EVK-001 evaluatoin board is available now.

www.rohm.eu