Automotive·AI Benefiting Power Semiconductor Stocks Surge 2 Trillion Won in Market Cap in One Day

Shares of Allegro MicroSystems Inc. (NASDAQ: ALGM), a U.S. power and sensing semiconductor company, surged 12.78% on the Nasdaq, closing at $51.82. Trading volume topped 2.31 million shares, driving its market capitalization up by roughly $1.4 billion to about $9.6 billion (approximately KRW 13 trillion).

In its fiscal 2026 fourth quarter results announced May 7, Allegro reported quarterly revenue of $243.2 million—a 26% year-over-year increase—and full-year sales of $890.1 million, up 23%. Earnings per share modestly beat analyst expectations, reaffirming the company’s growth trajectory. Major brokerages including UBS, Jefferies and Morgan Stanley have since raised their price targets from the mid-$50s into the low-$60s while maintaining “Buy” ratings, further fueling momentum. In mid-May, Allegro also appointed Robert Willett, former CEO of machine vision firm Cognex, to its board of directors, and its CFO is slated to present at TD Cowen’s Technology, Media & Telecom Conference on May 27—moves that have heightened institutional interest.

Founded in 1990 and headquartered in Manchester, New Hampshire, Allegro designs and manufactures magnetic sensor ICs and motor-driver power ICs focused on automotive and industrial applications. Its products serve electric vehicle powertrains, ADAS, factory automation and data center power management. At its February Investor Day, the company set targets of double-digit annual revenue growth and a fourfold increase in EPS over three to five years, positioning itself as a key beneficiary of trends in electric mobility, power efficiency and AI-driven data centers—an outlook that has underpinned its recent share-price rally.