SLVAFE7 September   2022 LM51551

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
    1. 1.1 Design Specification and Key Challenges
  4. 2High-Voltage Power Supply Design Using SEPIC
    1. 2.1 TI HV Supply Architecture Using SEPIC Topology
    2. 2.2 Switching Frequency Shift
    3. 2.3 Voltage Control by External Signal
  5. 3Test Result
    1. 3.1 Efficiency and Power Consumption (100 kHz vs 250 kHz)
    2. 3.2 Linearity of Output Voltages vs VBIAS
    3. 3.3 Output Ripple Measurement
    4. 3.4 Load Transient Test
    5. 3.5 Overload Protection
    6. 3.6 Thermal Image
  6. 4Summary
  7. 5References

3.1 Efficiency and Power Consumption (100 kHz vs 250 kHz)

Figure 3-1 shows the efficiency graphs under different output voltages. As illustrated, the peak efficiency reaches to approximately 83% at 75-V outputs. Figure 3-2 demonstrates the power consumption at different switching frequency. The power loss is lower at 100 kHz and decreases to 46 mW at maximum output voltage.

Figure 3-1 Efficiency Curve of SEPIC HV Power Supply
Figure 3-2 Power Consumption of Different FSW