This reference design is a power supply optimized specifically for providing power to eight 16-channel receive AFE ICs for ultrasound imaging systems. This design reduces part count while maximizing efficiency by using single-chip DC-DC converter + LDO combo regulators to set the LDO input just above the dropout voltage while taking full advantage of the LDO PSRR. In addition, ultra-low-noise LDOs help to attain the highest resolution possible from A/D conversion, leading to higher image quality. This design is capable of switching frequency synchronization with the master and system clock frequency to aid system designers apply simple filtering techniques to remove power supply switching noise on ground loops or use spreadspectrum clocking to reduce EMI. Additionally, the design implements an eFuse device, providing a simple and flexible means of overcurrent protection.
- Suitable for 12V input ultrasound system front end
- eFuse operating with input current limit of 4.2A
- Capable of powering eight AFEs for up to 128 channels (scalable channel count), supports power output of 36W
- Combo DC/DC converter + LDO ICs maximizes LDO efficiency by setting LDO input just above dropout voltage
- Uses high PSRR and ultra-low-noise (4.4 μVRMS) LDOs to attain highest resolution possible from A/D conversion
- Common synchronized power supply for all AFEs on same T/R board reduces board space while aiding noise reduction and EMI elimination