Boost DC/DC converter ideal for dry-cell applications

Ideal for dry-cell applications Boost DC/DC converter with built-in MOSFET

BU33UV7NUX is a boost DC/DC converter with built-in MOSFET featuring the lowest current consumption in the industry, making it ideal for electronic devices powered by dry-cell batteries such as electronic dictionaries, remote controls for home appliances, and gadgets (i.e. toys, accessories).

Samples/Evaluation Board

Evaluation Board BU33UV7NUX-EVK-101

In addition to samples of the BU33UV7NUX , an evaluation board integrating the BU33UV7NUX will be available for purchase through online distributors.

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Part No. Input Voltage Range Output Voltage Current Consumption Max. Load Current Operating Frequency Operating Temp. Range
BU33UV7NUX 0.6V to 4.5V 3.3V 7µA (MODE=L)
13µA (MODE=H)
50mA (MODE=L)
500mA (MODE=H)
800kHz -40 ℃ to 85 ℃


1.Low current consumption and low-voltage drive contribute to longer battery life

In order to prolong operating life with dry-cell batteries, ROHM leveraged original analogy design technologies and power system processes to achieve a current consumption of just 7uA, the smallest in the industry among functionally equivalent products. This makes it possible to increase battery life in conventional remote controls powered by 2 alkaline dry-cell batteries by approx. 1.3x over existing solutions, providing an extra 175 days of operation (ROHM study, assuming standby mode and a load current of 50uA). In addition, the BU33UV7NUX can be driven by input voltages as low as 0.9V and supports both single dry-cell and button-type lithium-ion battery sets. Plus, the built-in battery leak detection function makes it particularly suited for dry-cell applications.

Low current consumption and low-voltage drive contribute to longer battery life
2.Load current mode switching improves efficiency in a wide range of applications

A load current mode switching function is included that allows existing remote controls to support the latest high-performance LCD-equipped sets while delivering superior energy savings.
Adopting a low-power mode for standard products (50mA max. load current, 7uA current consumption, PFM*1 control), and automatically switching to high-power mode for high-performance (500mA max. load current, 13uA current consumption, PFM/PWM*1 switching control), make it possible to achieve high efficiency power conversion as high as 94% under a wide range of conditions.

Load current mode switching improves efficiency in a wide range of applications
*1) PFM (Pulse Frequency Modulation) / PWM (Pulse Width Modulation)
PFM is a voltage control method that can provide the benefit of reduced switching loss at light loads, while PWM is characterized by constant frequency that makes it easy to predict generated noise and subsequently set up countermeasures such as filters.


<Target Applications>

…and other sets driven by 1-2 dry-cell (1 to 3V) or button-type li-ion batteries

  • Electronic dictionaries
  • Remote controls
  • Electronic gadgets (i.e. toys, accessories)
  • Wearables
  • Electric toothbrushes