Broadcom, which makes chips for products such as smartphones, is bidding $70 per share for Qualcomm.
As yet Qualcomm has made no comment on the bid, which is the latest in a series of consolidations that have been sweeping the technology industry.
Broadcom is still waiting for regulatory approval to buy Brocade, while Qualcomm remains in talks to buy NXP Semiconductors.
In a statement Broadcom said that its offer for Qualcomm would stand whether or not the company went ahead with its proposed $38bn bid for NXP.
If Broadcom is successful its move would be seen as putting pressure on market leaders Intel and Samsung by creating the world's third largest chipmaker.
President and chief executive of Broadcom, Hock Tan said: "This complementary transaction will position the combined company as a global communications leader with an impressive portfolio of technologies and products.
"We would not make this offer if we were not confident that our common global customers would embrace the proposed combination."
