Diamond Electric Mfg. Co., Ltd. has developed a business card-sized, thin isolated bidirectional dc-dc converter (IBDC). The technology can substantially downsize and reduce the weight of dc-dc converters, which are essential for rechargeable batteries, and is expected to contribute to spreading electric vehicles (EVs) and smart grids.

By adopting high-frequency switching technology (up to 2MHz), Diamond Electric has developed an ultra-compact IBDC (93.5 mm x 60 mm x 10.5 mm excluding control circuit and heatsink).

Furthermore, the use of gallium nitride (GaN) power semiconductor enabled the achievement of high conversion efficiency (up to 95%) despite the high-frequency switching. By utilizing these technologies, the company expects to downsize the final product to 25% of other existing models.

Specifications include:

(click on table to enlarge)

In recent years, requirements of large-capacity batteries for EVs and smart grids are causing rechargeable batteries to have higher voltage. Therefore, demands are growing for higher-level isolation of dc-dc converters to ensure safety and meet safety standards.

In response, Diamond Electric has developed the new IBDC by fully utilizing its unique controlling technology (for which a patent is pending). The IBDC combines both charger and discharger circuits.

Expected applications include:

• EVs:

  • Onboard chargers

  • Onboard AC power supply

• Smart grids:

  • Battery system for household use

  • EV stations (V2H)

  • Uninterrupted power supply (UPS) system

  • Portable battery system