Accurate, High Coverage On-Chip Built-in Self-Test Adopting Precision-Enhanced Power Detection and Multipath Loopback for mmWave Radar IC Measurements

Testing of millimeter-wave integrated circuits become increasingly challenging as operating frequencies and channel counts continue to scale, leading to high test cost and long measurement time. This paper presents an on-chip built-in self-test (BIST) architecture that enables various testing with high accuracy using internal loopback paths, compact directional couplers, and distributed power detectors. To achieve accurate power sensing within a limited area, a novel directional coupler is proposed, achieving enhanced directivity to fully separate the induced and reflected signal. The proposed BIST architecture is fabricated in a 28-nm CMOS technology. Measurements have been done with BIST, obtaining less than 1 dB measurement error in key RF and IF parameters. The proposed BIST architecture has acquired 82% of internal test coverage.