RDA Microelectronics Inc said it received its second buyout offer after more than a month. The bid came from Tsinghua Unigroup Ltd. The Chinese state-owned firm funded by Tsinghua University offered USD 18 per share for the US-listed chipmaker trading on the Nasdaq. The buyout offer was at a 16% premium to RDA's most recent close of USD 15.55 per share.

Another Chinese state-owned company also offered to purchase the shares it does not already own in RDA Microelectronics in September. Pudong Science and Technology Investment Co Ltd made a bid of USD 15.5 per American Depositary Share for the chipmaker.

According to RDA, its board is still reviewing both bids. The company added that it has not made any decision on both offers.

RDA Microelectronics is a semiconductor company that manufactures radio-frequency chips for mobile and broadcast applications. Its roster of clients include Lenovo Group Ltd, Huawei Technologies and ZTE Corp.