SLOA284A january   2020  – may 2023 AFE5832 , AFE5832LP , ISO7741 , ISOW7841 , LM25037 , LM25180 , LM5180 , LM5181 , LM5181-Q1 , TX7316 , TX7332

 

  1.   1
  2.   Designing Bipolar High Voltage SEPIC Supply for Ultrasound Smart Probe
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Key Design Challenges
    2. 1.2 Potential Topologies for Generating High Voltage Supply
  5. 2Design of high voltage circuit using SEPIC topology
    1. 2.1 TI HV Supply Architecture Using SEPIC Topology
  6. 3Test Results
    1. 3.1 Efficiency and Load Regulation
    2. 3.2 Output Ripple Measurement
    3. 3.3 Load Transient Test
    4. 3.4 Noise Measurement
    5. 3.5 Thermal Performance
  7. 4Possible Variants of the Design
    1. 4.1 Option 1: Programmable Output Voltage
    2. 4.2 Option 2: Support Input From 1S Li-Ion Battery
    3. 4.3 Option 3: Output Voltage Up to ±100 V
  8. 5Layout Guidelines
  9. 6Clock Synchronization
  10. 7Summary
  11. 8References
  12. 9Revision History

4.3 Option 3: Output Voltage Up to ±100 V

In some cases ultrasound probes may require ± 100 V. The same limitations mentioned in option 2 are applicable. To achieve this, an intermediate boost stage is needed to boost the input to a minimum of 12 V to have a duty cycle of approximately 90%, as shown in Figure 4-4.

GUID-D0E85067-6509-44AA-9445-F56BDE3EA1B5-low.gif Figure 4-4 Case of ± 100 V
Note: the components ratings should be taken care in both these cases. For instance, the MOSFET in second case has to withstand about 113 V, and the coupling capacitor has to be rated for 20 V.