An On-Chip Power-Supply Noise Analyzer With Compressed Sensing and Enhanced Quantization

This article discusses the on-chip measurement of the power-supply noise (PSN) and demonstrates a scalable PSN spectrum analyzer with significantly improved speed and accuracy. Compressed sensing is exploited in the autocovariance-based measurement since the cyclostationary PSN is sparse. A six-level voltage-controlled oscillator (VCO)-based phase quantizer is proposed to improve the noise performance. The accumulation of measurement points is enhanced with multi-slice parallel quantization. A calibration-free nonuniform-sampling clock generator is implemented on-chip. With only one external clock reference, the 40-nm PSN analyzer achieves a 20-GHz bandwidth with 2-MHz spectral resolution and 0.23-μ V ²/√MHz noise floor. With a comparable accuracy, the measurement time has been orders of magnitude shortened to the sub-second level, enabling rapid in situ measurement of on-chip PSN with speed-accuracy scalability.