We're developing a board with the QCA4010, and are production-testing the boards. (EVM measurements). They seem to fail this test and the Qualcomm application engineer blames our use of 100ohm differential transmission lines between the QCA4010 and the balun. However, the documentation (80-y9905-8_c_rb04_hardware_reference_guide.pdf section 3.3) mentions that everything should be 50ohm, without mentioning whether this is the differential or single-ended impedance. The layout pictures clearly show similar tracewidths before and after the balun, which tells us that the impedance used is actually 100ohm differential chip-balun and 50ohm single-ended balun-antenna. Can anyone shed some light?