Carlsbad-based MaxLinear, a developer of radio frequency (RF) and mixed signal semiconductors, said Tuesday that it has added Donald Schrock to its board. Schrock has previously served at Qualcomm, Motorola, GM-Hughes Aircraft, Burr-Brown, and Applied Micro Circuit Corporation. At Qualcomm, Schrock was Group President of Qualcomm's CDMA Technologies Group. Schrock is also on the boards of Integrated Device Technology and Patriot Scientific.