Rohm Has Developed A Boost Dc / Dc Converter Capable Of 1.3 Times Longer Battery Life

ROHM, a world-renowned semiconductor manufacturer, develops battery-operated electronic devices such as electronic dictionaries, home appliance remotes and small objects (toys and accessories) to create a step-up DC / DC converter with MOSFETs that consumes as little current as the industry's lowest level * 1) "BU33UV7NUX".

The "BU33UV7NUX" is a step-up power supply IC that outputs the input voltage (1V ~ 3V) of one to two dry batteries as the 3.3V voltage required for driving a microcontroller. This product has been developed to minimize current consumption to extend the operating hours of dry-battery applications, delivering the industry's smallest 7μA current consumption in equivalent products. When 2 alkaline dry battery-operated remote controllers are on standby (50μA load current) Battery life can be extended up to 175 days (from 540 days to 715 days) compared to typical products (ROHM survey data). In addition, the load current mode switching function is also provided, making the same remote control suitable for high performance products using liquid crystal panels and the like, which greatly contributes to more energy saving for a large number of dry battery applications from standard products to high performance products.

The product has been put into mass production on the scale of 1 million per month (sample price 500 yen / month: excluding tax) since December 2017. The production base of the pre-process is the ROHM headquarters plant (Kyoto, Japan), and the post-production base is ROHM Electronics Philippines, Inc. (Philippines).

In the future, ROHM will continue to develop high-performance, high-reliability products that utilize the advantages of analog technology to contribute to the energy saving in society.

<Background>

In recent years, mobile devices such as smartphones and wearable devices have been increasingly used in rechargeable secondary batteries such as lithium ion batteries (LiBs). In electronic devices such as electronic dictionaries, home appliance remotes and small objects, with the diversification of applications and the expansion of overseas markets, the use of dry-cell batteries has surpassed that of ever before due to the ever-increasing performance and function of these applications. Carrying the power supply IC's energy-saving performance requirements are getting higher and higher.

ROHM uses many years of accumulated analog circuit technology and power system technology advantages, has been committed to the development of market demand to meet the various power IC products. The use of these technologies, but also the development of the current equipment used in dry battery power IC.

<Features Details>

1. Consumption of current and drive voltage is lower, helps to extend the battery life

Using ROHM's analog design technology and power system processes to reduce current consumption, consuming only 7μA, the industry's smallest class, consumes only the lowest power in the industry, enabling longer battery life. This allows two alkaline batteries driven remote control standby time (load current 50μA) life of about 1.3 times longer than the average product (up to 175 days) (ROHM survey data). In addition, the power IC driven by a low input voltage of 0.9V, not only supports button-type lithium battery, but also supports the use of a dry battery applications. But also equipped with a battery leakage detection. All in all, this is the best power IC for dry cell applications.

2. With load current mode switching, efficient support for many applications

For example, equipped with a load current mode switching function, the same remote control can also be used for high performance products such as liquid crystal panels. Just switching the MODE pin can help improve the energy efficiency of many battery applications from standard products to high performance products.

Low Power Mode (Max Load Current 50mA, Current Consumption 7μA, PFM * 2) for Standard Products, High Power Mode for High Performance Products (Maximum Load Current 500mA, Current Consumption 13μA, PFM / PWM * 2) Switching control) enables efficient power conversion up to 94% in a wide range of conditions.

<Application Example>

Electronic Dictionary Remote Control Small Objects (Toys, Accessories)

Wearable Devices Electric toothbrushes

And so on with 1/2 batteries (1 ~ 3V), button-type lithium battery for all applications

Product Type Input Voltage Range Output Voltage Current Consumption Maximum Load Current Operating Frequency Operating Temperature Range

BU33UV7NUX 0.6V ~ 4.5V 3.3V 7μA (MODE = L)

13μA (MODE = H) 50mA (MODE = L)

500mA (MODE = H) 800kHz -40 ℃ ~ 85 ℃

<Evaluation Board Information>

Beginning of sales in January 2018 onwards

Network sales platform AMEYA360, Right IC

Evaluation Board Model BU33UV7NUX-EVK-101

<Glossary>

* 1) DC / DC converter

A type of power IC used to convert a direct current (DC) voltage to a direct current voltage. There are generally buck type (voltage drop) and boost (make the voltage rise) two.

* 2) PFM (Pulse Frequency Modulation), PWM (Pulse Width Modulation)

PFM is a voltage control method that has advantages in reducing switching losses at light loads. PWM is also a voltage control method, the frequency is fixed, easy to predict the noise interference, so the noise is easy to use additional filters and other countermeasures.