According to sources close to the situation, well-known tech exec Jon Rubinstein will be joining the board of Qualcomm, the San Diego-based chipmaker that has gotten a big boost of late for its role in the explosion of mobile devices. Rubinstein is an interesting and logical choice for Qualcomm, having been a high-profile player for a long time in the mobile space, beginning with his work on the iPod while at Apple. After he left his last job at Hewlett-Packard last year, though, he has been very low-key. For Qualcomm, the selection of Rubinstein to join the board is something to watch, as he is the second exec from Silicon Valley to be tapped by the company recently. In March, Qualcomm hired tech investor Laurie Yoler as SVP of business development, making her “responsible for augmenting existing business relationships in Silicon Valley, as well as developing new strategic business opportunities for Qualcomm in the region.”