AN4006

List of figures

Doc ID 022454 Rev 1

3/19

List of figures

Figure 1.

High-power converter schematic: detail of the input section including data transformers,

bridges, protection and optional CM choke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 2.

High-power converter: detail of the PoE converter based on active-clamp forward topology

with self-driven synchronous rectification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Figure 3.

Efficiency measurements at 48 V input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 4.

Efficiency of the different circuits on the converter input stage. . . . . . . . . . . . . . . . . . . . . . 10

Figure 5.

Booster current characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 6.

Booster power dissipation vs. input current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 7.

Startup with 0 A load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 8.

Startup with 10 A load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 9.

Primary-side power MOSFET waveforms at 0 A load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 10.

Primary-side power MOSFET waveforms at 16 A load . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 11.

Secondary-side power MOSFET waveforms at 0 A load . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 12.

Secondary-side power MOSFET waveforms at 16 A load . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 13.

Output ripple measurement at 0 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 14.

Output ripple measurement at 16 A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 15.

Output ripple measurement at 16 A with infinite persistance . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 16.

Control loop of the converter at 48 V input and 18 A output . . . . . . . . . . . . . . . . . . . . . . . . 17

Figure 17.

Response of the converter to a 8 A - 16 A load transient . . . . . . . . . . . . . . . . . . . . . . . . . . 17