Integrated 16-Channel Transmit and Receive Beamforming ASIC for Ultrasound Imaging

In commercial ultrasound systems, the multielement transducer array is connected to analog front end electronics using long-wire high voltage coaxial cables. This paper presents the circuit design of 16-channel Transmit (Tx) and Receive (Rx) beam forming ASIC (Application Specific Integrated Circuit) that can be integrated in ultrasound probe head which reduces the number of coaxial cables. The proposed modular design for programmable 16-channel transmit beam former operates at medical frequencies in pulse-echo mode and provides user control of transmit parameters such as transmit pulse length, pulse pattern, transmit frequency, and mode of excitation. The receive beam former implements delay and coherent sum of the digitized echoes from 16 adjacent transducer elements to form scan lines required for image reconstruction. The proposed architecture of the Rx beam former design provides great flexibility for beam forming, such as receive focusing with predetermined delay profile. Each transmit channel can be programmable to give a maximum delay of 163.85 s with 1.25 ns delay resolution. The proposed design implements dynamic receive focusing with minimum time delay resolution of 3.125 ns for 40 MHz input data rate. The proposed ASIC of integrated Tx and Rx beam former is implemented in UMC 130 nm technology using Synopsys ICC and Design Compiler. The implementation reports show that the area is 5.29 mm2, power dissipation is 38 mW.