The circuit protection equipment maker has invested $15m in portfolio company Monolith Semiconductor, taking a majority stake in the process.

Circuit protection equipment producer and existing investor Littelfuse has provided $15m in funding for US-based silicon carbide technology developer Monolith Semiconductor, giving it a majority stake.

Founded in 2012, Monolith supplies silicon carbide diodes and metal-oxide-semiconductor field-effect transistors that help inverters and motor drives to operate at higher switching frequencies than conventional silicon, making them more efficient and affordable to run.

Ian Highley, Littelfuse’s chief technology officer and general manager of its semiconductor products division, said: “We are pleased to…