BD83070GWL Buck-Boost DC-DC Converter Achieves Amazing Power Savings Performance : High Efficiencies at All Load Levels Maximized Operating Times of Battery-Driven Equipment

The BD83070GWL is a buck-boost (step-up/step-down) DC-DC converter IC with an internal MOSFET, developed for use with battery-driven mobile devices, wearable equipment, and IoT equipment. Through buck-boost operation the battery energy is utilized to maximum effect, while realizing the industry’s highest efficiencies* and among the lowest current consumption levels in the industry over a broad range of load conditions, from light to heavy loading. As a result, operating times for battery-drive equipment can be greatly extended. *ROHM survey, July 2019

The lineup of high-efficiency, ultra-low power consumption DC-DC converter ICs developed specifically for use in battery-powered applications already includes the BU33UV7NUX for step-up use and the BD70522GUL for step-down applications, among others. The buck-boost BD83070GWL is a new product that supplements the lineup of high-efficiency, ultra-low power consumption DC-DC converter ICs.

Securing Sufficient Equipment Operating Time While Allowing For Compact Batteries

In recent years, electronic devices that run on batteries have come to be used in a wide variety of areas–from mobile devices to wearable equipment, to IoT products. Devices mounted on these items are required to be compact so as to improve design and secure space for new functions, and must also reduce power consumption insofar as possible in order to improve the length of battery use.

In order to extend battery operating time, it is essential that the equipment power consumption be reduced and the battery energy be used to the absolute maximum. The various devices that constitute an equipment system use different methods to attempt to reduce power consumption, but it is extremely important that power consumption be reduced in a power supply that directly converts energy from a battery to feed power to another device.

In order to reduce power consumption in a power supply, the power consumption of the power supply itself must be suppressed to improve efficiency, regardless of the load conditions and mode of operation. When power is input from a battery, the input voltage varies from an initial voltage that is higher than the preset output voltage to a voltage below the preset output voltage. Hence in order to make maximum use of the battery energy, it is extremely useful to employ a buck-boost converter that performs highly efficient step-down operation when the input (battery) voltage is higher than the preset output voltage, but switches to highly efficient step-up operation when the input falls below the preset output voltage, so as to maintain a constant output voltage. In other words, a buck-boost converter that is capable of performing both voltage step-up and step-down with high efficiency, regardless of the load level, can be said to be a power supply that makes maximum use of the remaining battery energy.

BD83070GWL Buck-boost DC-DC Converter Achieves High Efficiency Over a Broad Range of Load Conditions

＜Features＞

• ・Through incorporation of a low-loss MOSFET based on a 0.13 μm BiCDMOS process for power devices, the following are achieved:

  –Achievement of an industry-high power conversion efficiency of 97% at an operating load current of 200 mA, which is common in electric toothbrushes, electric shavers and the like

  –High efficiencies of at least 90% over a broad range from light loads of 100 μA to the maximum load of 1 A

  –Battery operating time extended by 1.53 while in application standby (assuming load current of 100 μA) (ROHM survey)

• ・A low-power consumption current and automatic PFM/PWM control technology are combined to accomplish:

  –Current consumption of 2.8 μA typ (VIN=3.6 V, Auto-PFM/PWM, no load), among the best in the industry for a buck-boost power supply IC

• ・Use of ROHM’s unique “X Ramp PWM Control” technology to achieve seamless buck-boost transitions
• ・Onboard heat, overvoltage, overcurrent, and UVLO protection

＜Basic specifications＞

• ・Input voltage range: 2.0 V to 5.5 V
• ・Output voltage: 2.5V or 3.3V (pin selectable)
• ・Output current: 1 A (Max)
• ・Switching frequency: 1.5 MHz (Typ)
• ・Current consumption: 2.8 μA (Typ)
• ・Operating temperature range:－40℃ to ＋85℃
• ・Ultra-compact 12-pin UCSP50L1C package (1.20mm × 1.60mm × 0.57mm)

＜Application examples＞

• ・Coin battery-operated electronic devices such as IoT products
• ・Electronic devices using single-cell Li-ion batteries
• ・Electronic products running on dry cells, such as toys, electric toothbrushes, and the like

＜Evaluation Board Information＞
An BD83070GWL-EVK-001 evaluation board with the BD83070GWL installed can be purchased from online retailers. For details, refer to the Support Page.

＜Lineup of Power Supply ICs Featuring Power-Saving Performance for Mobile Devices＞

Function	Part No.	Current Consumption	Input Voltage	Output Voltage	Max Output Current	Operating Frequency	Max Efficiency	Package
Buck-boost	BD83070GWL	2.8μA	2.0～5.5V	2.5, 3.3V	1000mA	1.5MHz	97% @200mA	UCSP50L1C (1.2mm×1.6mm)
Boost	BU33UV7NUX	7μA (MODE=L) 13μA (MODE=H)	0.6～4.5V	3.3V	50mA (MODE=L) 500mA (MODE=H)	800kHz	91% @1mA	VSON010X3020 (3mm×2mm)
Buck	BD70522GUL	0.18μA	2.5～5.5V	1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.3V	500mA	1MHz	90% @10μA	VCSP50L1C (1.76mm×1.56mm)