A 32-40 GHz 7-bit CMOS Phase Shifter with 0.38dB/1.6° RMS Magnitude/Phase Errors for Phased Array Systems

This paper presents a 32-40GHz 7-bit programmable passive vector synthesis phase shifter in 65 nm CMOS. It mainly consists of a compact differential hybrid quadrature generator (HQG) based on folded transformer and a 12-bit binary weighted passive vector modulation (PVM) composed of two 6-bit phase invariant passive variable gain amplifiers (VGAs). Two additional inter-stage matching transformer are placed between the HQG and VGAs in order to obtain wider bandwidth and better amplitude and phase performances. The measurement results show a RMS phase error of 0.45° to 1.6° over 32-40 GHz, and 0.45° to 1.1° over 33-39 GHz, whereas covering 360° phase range at 2.8° resolution. The measured variation of insertion loss (IL) is below ±0.8dB over 32-40 GHz and below ±0.6dB over 33-39 GHz, the RMS magnitude error is less than 0.38 dB over 32-40 GHz. The power consumption is zero and the core die area is 630 um*220 um.