The largest shareholder of Vitesse Semiconductor Corp. has purchased an additional 1.6 million shares concurrent with a secondary offering, according to a regulatory filing.

The Camarillo company, which makes integrated circuits for internet communications, said William Martin, chairman of Raging Capital Management LLC in Rocky Hill, N.J., purchased the shares on June 12 at a price of $3.35 each.

The purchase gave Raging Capital a total of 14.3 million shares or about 25 percent of the company’s outstanding shares. However, the company completed a secondary offering on Tuesday of roughly 7.5 million shares, also priced at $3.35. The additional shares will reduce Martin’s stake to 22 percent.

Vitesse plans to use proceeds from the offering – estimated at $28.7 million – for working capital and general corporate purposes.

Shares closed up 4 cents, or 1 percent, to $3.51 on the Nasdaq.