Morrison & Foerster and Fenwick & West have the lead roles in Tsinghua Unigroup Ltd.’s proposed $1.78 billion acquisition of Chinese mobile phone chip maker Spreadtrum Communications Inc.

Shanghai-based Spreadtrum has agreed to Tsinghua’s offer of $31 per share. Spreadtrum sells most of its chips in China and Korea, and manufactures for companies including Samsung Electronics and HTC Corp.