Maxim Integrated Products has a SiGe variable-gain amplifier with on-board continuous-wave Doppler (CWD) beamformer designed for use in ultrasound-imaging applications.

The MAX2036/MAX2038 combine the linearity and noise performance of the previously introduced MAX2035/MAX2037 VGAs with the added functionality of an on-chip, octal quadrature mixer array and programmable LO phase generators.

During normal operation, the MAX2036/MAX2038 are configured such that either the VGA path is enabled while the mixer array is powered down (VGA mode), or the quadrature mixer array is enabled while the VGA path is powered down (CW mode). When in CW mode, the LO phase dividers can be programmed to allow 4, 8, or 16 quadrature phases for optimal beamforming resolution.

The devices possess the necessary dynamic range and noise performance to detect Doppler shifts ranging from 100kHz to less than 1kHz. The mixers and LO generators are designed to have exceptionally low thermal and jitter noise performance of -155dBc/Hz at 1kHz offset from a 900mVp-p, 1.25MHz carrier signal.

The MAX2036/MAX2038 are available in 100-pin TQFP packages.