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

3.1 Efficiency and Load Regulation

Figure 3-1 and Figure 3-2 shows the efficiency and load regulation of the power supply with symmetrical loads on the positive and the negative rail. The load is varied from 0 to 25 mA on each rail. The peak efficiency observed is ~75 % and worst case load regulation is 1.99 %. The positive and negative outputs are symmetrical within 1% with respect to each other.

GUID-7A1CE244-A095-4D7C-B365-2F4C91E6E06F-low.gifFigure 3-1 Efficiency Curve of SEPIC HV Power Supply
GUID-ED6A1899-8427-41DC-9E96-050B028E3C4C-low.gifFigure 3-2 Load Symmetry of SEPIC Showing Accuracy of Less Than 1% and Load Regulation Less Than 2%