Japan’s power-semiconductor comeback: three giants tee up a national consolidation

Deal memo signals a strategic regrouping — not a done deal

ROHM (罗姆), Toshiba (东芝) and Mitsubishi Electric (三菱电机) have signed a memorandum to explore business and operational integration around power semiconductors, reportedly aiming to create a combined entity that would hold roughly 10% of the global market and become the world’s second‑largest alliance after Infineon (英飞凌). It has been reported that the memorandum is preliminary: structure, terms and timing remain subject to further negotiation and regulatory approvals. Still, the move sends a clear message — Tokyo is trying to reassemble scattered strengths into a single, more competitive platform.

Why now? Market structure and national strategy

Power devices are no longer niche industrial parts. They are the switching heart of electric vehicles, energy storage, PV inverters, rail traction and data‑centre power supplies. Omdia data show Infineon leading at about 17% market share, while Mitsubishi Electric sits at about 4.6%, Toshiba 2.6% and ROHM 2.5%. It has been reported that ROHM’s 2024 results were badly hit by EV demand swings and that the company forecast a fiscal‑year loss, prompting a management change and renewed calls for consolidation. Japan’s Ministry of Economy, Trade and Industry has also publicly urged consolidation, and a 2025 policy paper reportedly named ROHM, Toshiba and other players as the basis for domestic reorganization.

Complementary capabilities — and a wider industrial context

The strategic logic is not mere arithmetic. ROHM brings SiC roadmap and 8‑inch ambitions, Toshiba has broad automotive electrification coverage from MOSFETs to SiC modules, and Mitsubishi Electric is a long‑time leader in high‑voltage, high‑reliability power modules. It has been reported that Denso (电装) is also a catalyst — holding near‑5% of ROHM and exploring strategic options — which ties the consolidation to Japan’s dominant automotive supply chain. Geopolitically, this consolidation sits against a backdrop of export controls, subsidy competition and supply‑chain diversification, as governments in Tokyo, Brussels and Washington weigh industrial security alongside market competition.

What it means for China

China’s advantage remains demand density: Silan Micro (士兰微), BYD Semiconductor (比亚迪半导体) and China Resources Microelectronics (华润微) are scaling SiC, GaN and module efforts amid fast EV, PV and storage deployment. But the Japanese move raises the bar in high‑end, system‑level competition — long‑life modules, global qualification and integrated platform deals. Will Chinese firms simply compete on price and device replacement, or can they convert massive in‑market validation into modular platforms, long‑cycle reliability data and international trust? The answer will determine whether Japan’s re‑aggregation becomes a new bottleneck — or a spur for China to accelerate platformization and certification.