Mixed-Signal Design Verification: Leveraging the Best of AMS and DMS

Analog and mixed-signal (AMS) design and verification methodology exists from the very beginning of mixed-signal IC design practice, but its role has gradually become less clear since the emerging dominance of digital mixed-signal (DMS) methodology. In this paper, we seek to analyze individual roles of AMS and DMS, why both are necessary and complementary, and how we can take advantage of each flow’s strength to optimize verification resources and job efficiency. We argue that analog behavior models are the key to the success of mixed-signal design verification (MSDV), and the availability and quality of models for analog circuits have large impact on the flow to be used and the quality of the MSDV. We describe how we can bring the AMS and DMS flows together under single test infrastructure with the UVM platform. Additionally, the typical activities and responsibilities of an MSDV team are outlined as well. It is the interest of this paper, using a typical mixed signal chip design we have recently developed at Analog Devices as an example, to present the spectrum of MSDV activities. By presenting specific tasks and analyzing their roles in the full chip verification, we wish to provide some insight on how AMS and DMS can work together, and how we can combine the two flows to optimize resources and tasks. Finally, we present our results by analyzing test coverage and bug reports from AMS and DMS flows; and conclude how both AMS and DMS play an important role in the MSDV.

Rock Shi, Analog Devices
Padmashree Bhinge, Analog Devices
Preston Birdsong, Analog Devices
Geeta Chaitanya, Analog Devices
Kunal Jani, Analog Devices