In our actual use, the measured efficiency of this chip is very different from the datasheet. The above figure 1 is the schematic diagram. Compared with the datasheet, the main difference is the DCR of the inductor, but the actual effect of the DCR is compared. The efficiency impact is generally 2-3 Points.
The actual test environment is as shown in Figure 2 above. Therefore, the input is connected to a DC source and the output is connected to an electronic load. The figure shows the measured efficiency of 82.87%. The efficiency of the datasheet 1V output Figure 3 shows that the efficiency at this point is about 91.5%, which is quite different.
Please help analyze why there is such a big difference. Figure 4 above is a set of measured efficiency graphs.
In addition to the displayed filter capacitors, there are several 22uF+1uF capacitors on the load side (the load is an ASIC chip, which has been removed during the test).