Analog mixed-signal circuits in advanced nano-scale CMOS technology for microprocessors and SoCs

Scaling of CMOS technology has made major innovations in the last decade with the introduction of strained silicon and high-k metal gate, however at the same time an increasing amount of complex analog mixed-signal circuit functionality has been integrated on microprocessors and SOCs. Examples of the key analog mixed-signal circuit functional blocks implemented in advanced 45nm and 32nm logic CMOS on microprocessors and SOCs are described. Techniques that overcome the challenges of the low supply voltage and dimensional scaling in 45 nm and 32nm CMOS include the use of the digital transistor for analog circuits, the use of “digital assist” logic for calibration and differential pair offset cancellation. The co-optimization of design techniques and process enhancements for high performance RF wireless circuits integrated on SOCs was employed to manage complexity and cost.