A single-chip time-interleaved 32-channel analog beamformer for ultrasound medical imaging

This paper proposes a single-chip time-interleaved 32-channel analog beamformer for ultrasound medical imaging. The proposed analog beamformer circuit consists of multiple sub analog beamformers which are time-interleaved for beamforming of multiple focal points on a scan line. Each sub analog beamformer executes beamforming for an assigned focal point on a scan line sequentially by sampling and summing the ultrasound echo signals of 32 channels. The proposed 32-channel analog beamformer circuit was fabricated in a single chip with an active area of 15.75 mm² in a 0.13 μm standard CMOS process. The total power consumption of the chip is 150 mW with a 1.2V supply. The delay resolution of the implemented analog beamformer circuit is 1/200 of the ultrasound carrier period. The analog beamformer operation was successfully verified through measurements by applying the emulated ultrasound echo signals taken from a commercial ultrasound imaging device through commercial DAC chips to the fabricated chip.