This reference design is a digitally programmable non-isolated power supply for powering ultrasound transmit circuit. It uses flyback power supply topology with the a single transformer to generate dual programmable high voltage (HV) up to the absolute value of 100 V. This design is targeted for low-power portable ultrasound scanners. The design can deliver a maximum continuous power of 25 W with 12.5 W each on individual rails. The HV rails are programmable from 0 V to ±100 V through a set DC voltages. The programmability through DAC can be implemented using 12-bit DACs which can be referenced from reference design TIDA-01352. All the power supply rails are capable of synchronizing to a master clock. This design is scalable and modular allowing the same supply to be duplicated or removed, depending on number of channels and number of pulser levels.
Features
- Operates from 24-V supply with wide range of frequency from 100 kHz to 500 kHz with digitally programmable dual output from 0 V to +/- 100 with peak efficiency of 87% at full load
- Non-isolated common power supply for bias and pulser driver (to support B-mode, CW-mode and elastography mode)
- Capable of powering up to 192 digital pulser channels through flyback topology that enables scalability for lower/higher channel counts
- Capable of switching frequency synchronization with ultrasound master or system clock frequency which helps in better harmonics rejection
- Modular design allowing same supply to be duplicated or removed depending on number of levels for the pulser
- Current mode control provides superior bandwidth and transient response with cycle-by-cycle current limiting