Japanese semiconductor company Renesas Electronics Corp. said Thursday it will acquire U.S. software firm Altium Ltd. for about 9.1 billion Australian dollars ($5.9 billion). Altium provides development tools for designing electronic devices. Under the acquisition deal, Renesas aims to expand sales of its chips to firms that utilize Altium’s designing tools, a Renesas spokesperson said. The Japanese company said it will acquire all outstanding shares of the California-based firm, originally founded in Australia, in the second half of this year, and make Altium a wholly-owned subsidiary. Renesa…