For chip design? Yes, I have (among other jobs as a hardware design engineer, and systems engineer - in the high-speed digital signal processing realm). Developed full-custom very high-speed very highly pipelined CMOS, with our own tools and libraries. Resulting in a variety of multi-channel high-speed digital downconverters and up converters, digital filters, etc for direct-sample A/D-converted IF and RF spectrums, QAM modulators, digital pre-distortion to correct power amplifier non-liearities, etc. Tape-outs went to various contract fabs as we were a small company. Devices were initially used by the military and govt agencies (they could afford the high prices - $300 for a four channel DDC), and then commercial wireless infrastructure on the BTS side, as our company grew.
SMH???
OK, how about you?