PMC-Sierra's ( PMCS) head of finance is resigning, the company announced after Thursday's market close. The Santa Clara, Calif., chipmaker said that Alan Krock, who joined PMC as CFO in 2002, is leaving the company for personal reasons. Krock will stay on through a "reasonable transition period," the company said. PMC also provided an update to its second-quarter financial guidance in the same announcement. PMC said it expects revenue to be at the midpoint of its previously set range of $108 million to $112 million, resulting in sales of $110 million. The figure does not include an expected $8.5 million to $9 million in revenue from PMC's acquisition of Passave in May. Shares of PMC closed the regular trading session up 0.3%, or 3 cents, at $9.04. In recent after-hours trade, shares were off 3.7% to $8.70.