What is the BD9x-LB series of industrial DC/DC converters?

"DC/DC converters" are essential for power supply design, and semiconductors with high withstand voltage are required for 48V bus lines used in industrial equipment and communication infrastructure. Especially in recent years, due to the growing awareness of energy conservation, the adoption of high-efficiency power devices and power supply ICs is progressing in industrial applications that handle large currents.

The problem is not only reliability and durability, but also high voltage resistance that can withstand sudden surge voltages such as lightning. ROHM sells the BD9x-LB series of DC/DC converters for industrial use, and the BD9G341AEFJ is the product with the highest withstand voltage.

The BD9G341AEFJ was developed for industries such as communication base stations, where traffic is increasing due to increased demand for smartphones, and factory production systems, which are becoming more sophisticated with the introduction of FA (factory automation). Here, we will explain the 80V class high voltage DC/DC converter "BD9G341AEFJ" from the "BD9x-LB series".

Main features and advantages of BD9G341AEFJ, the highest voltage product of the BD9x-LB series

"BD9G341AEFJ" is a DC/DC converter with built-in 80V high voltage MOSFET developed for businesses that handle high power. This is ROHM's highest withstand voltage product, and since it can secure a sufficient voltage margin even with the 48V bus line used in communication infrastructure, it is effective for designing safe power supplies for communication base stations and industrial equipment.

The power efficiency is 19% at maximum and 1.5% at stable use compared to general products (both at 300kHz oscillation frequency, 48V power supply voltage, and 5V output voltage). It achieves the industry's highest efficiency for an 80V class DC/DC converter, contributing to energy savings in industrial equipment.

In addition, it employs a unique protection function that protects the IC from overheating and damage caused by shorting (contacting) the output pin. The small 8-pin package is effective in reducing the mounting area and the number of peripheral parts, and it is a DC/DC converter that combines high voltage resistance, high efficiency, high reliability, and high ease of use.

Its small size allows for a high degree of freedom in power supply design, and it has a sufficient voltage margin for input voltages of 76V and 48V lines, making it ideal for motor applications with large surge voltages.

High withstand voltage of 80V, the highest class in the industry

By adopting 0.6μm high voltage BiCDMOS, it achieves 80V high voltage, which is the highest class in the industry for non-isolated type. This is a step-down 1-channel switching regulator with built-in power MOSFET that supports an input voltage rating of 80V (76V input). The input voltage can support up to 76V, ensuring a sufficient voltage margin even with a 48V bus line, which is common in communication base stations and FA equipment. High reliability can be achieved because there is a margin for sudden surge voltages.

High-efficiency design for energy saving

As an 80V class DC/DC converter, it achieves the highest class of voltage conversion efficiency in the industry (*October 2015 ROHM Co., Ltd. survey), up to 19% higher than general products, and 1.5% higher even in stable use (both 300kHz oscillation frequency, 48V power supply voltage, and 5V output voltage). It improves the voltage conversion efficiency in all load bands and realizes energy saving of industrial equipment.

Unique protection circuit improves reliability

The protection function of a general DC/DC converter cannot control the heat generated when the output pins are shorted (contacted), and the IC heats up, eventually leading to destruction. However, "BD9G341AEFJ"'s unique protection circuit suppresses heat generation in the event of a short circuit and prevents damage to the product. When a short circuit is detected, the input to the IC is stopped for 20msec to suppress heat generation and prevent damage to the circuit.

Compact 8-pin package effective in reducing mounting area and peripheral components

As an 80V class high voltage DC/DC converter, it uses a simple and small 8-pin package (width 4.9mm x depth 6.0mm x height 1.0mm) to reduce the mounting area and the number of peripheral parts. This reduces the number of peripheral parts required from 17 to 12, offering significant benefits such as reduced design man-hours and increased flexibility in mounting.

Evaluation board "BD9G341AEFJ-EVK-101"

BD9G341AEFJ-EVK-101 is an evaluation board for evaluating the DC/DC converter "BD9G341AEFJ". It can be mounted on your existing system board or on a prototyping breadboard.

Application example

• Communication infrastructure that requires a 48V class power supply, such as communication base stations, office phones, and routers.
• Industrial equipment that requires a 48V class power supply, such as FA equipment and industrial robots
• Motor applications with large surge voltages, such as electric vehicles and vacuum cleaners

Product Line

ROHM's "BD9x-LB Series" is a step-down DC/DC converter series ideal for industrial equipment applications. In addition to evaluation boards and sample sales, various contents necessary for design, such as web simulations, SPICE models, and application notes, are available for easy design and evaluation.

*Each "PART NO." will be moved to the official site of ROHM Co., Ltd.

Related Links

Web Simulation ROHM DC/DC Designer

10 models for industrial machinery have been added to the design simulation tool "ROHMDC/DC Designer" that allows you to build a circuit online when selecting a DC/DC IC for power supply design and evaluate it before building the actual parts. Basic circuit characteristics such as loop stability, transient response characteristics, and efficiency characteristics can be checked in 3 simple steps. You can start the tool from the D button in the model list on the ROHM website.

Web Simulation ROHM DC/DC Designer

Support content

In addition to simulation tools, content such as SPICE models, evaluation board user guides, and application notes are posted on the product page. We support your design with rich content. Each content can be downloaded from each product page.

ROHM support content

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