(Corrects to say RDA is a U.S.-listed chipmaker, not a U.S. company)

Nov 6 (Reuters) - U.S.-listed chipmaker RDA Microelectronics Inc said it received an $18 per share buyout offer from China's state-owned Tsinghua Unigroup Ltd, which is funded by the Tsinghua University, marking it a second such bid in more than a month.

The offer represents an almost 16 percent premium to RDA's Wednesday close of $15.55 on the Nasdaq.

In September, RDA Microelectronics said China's state-owned Shanghai Pudong Science and Technology Investment Co Ltd offered to buy the shares of the chipmaker it does not already own at $15.50 per American depositary share.

RDA said no decision has been made with respect to either offers, adding that its board is evaluating both the proposals.

RDA Microelectronics, which makes radio-frequency chips for mobile and broadcast devices, counts Huawei Technologies , ZTE Corp and Lenovo Group Ltd as customers. (Reporting by Sakthi Prasad in Bangalore; Editing by Supriya Kurane)