Thomas Weisel downgraded SigmaTel (SGTL

) to peer perform from outperform, explaining that the semiconductor company faces challenges such as increased competition and weaker-than-expected demand.

Analyst Jason Pflaum believes the stock already discounts a healthy dose of bad news, but he expects the company to announce near term downward earnings estimate revisions. He believes the shares are fairly valued at 22 times his 70 cents earnings per share estimate for 2006.