SigmaTel (SGTL delisted from NASDAQ after 2008 acquisition by Freescale Semiconductor) was a System On a Chip SOC electronics and software company headquartered in Austin, TX, that designed AV media player/recorder SOCs, reference circuit boards, SOC Software Development Kits, media player software apps, and controller chips for multifunction peripherals. SigmaTel was Austin's largest IPO as of 2003 when it became publicly traded on NASDAQ.