San Jose-based Cadence Design Systems said last week that it has named Lip-Bu Tan as the firm's President and CEO. Tan is chairman of venture capital firm Walden International, and has been on Cadence's board since 2004. According to Cadence, Tan will remain a member of its board of directors. Cadence has been looking for a new CEO for several months, and Tan was part of an interim team to lead Cadence since October. That team--which Cadence called the Interim Office of Chief Executive--has now been disolved. Tan has been on Cadence's board since 200. According to Cadence, Tan will continue to serve as chairman of Walden International.