AN1895 datasheet(11/16 Pages) STMICROELECTRONICS

11 / 16 page

AN1895

Getting started with the evaluation board

11/16

Figure 9.

Line current waveforms @ POUT = 180W

Figure 10.

Line current waveforms @ POUT = 70W

Note:

Note that input LC filter is provided only to clean the line current waveform enough to

prevent the measurement system from being misled by an excessive noise level. The filter is

not designed nor tested for EMI compliance.

The board, as is, is able to handle properly an output load as low as 15 W. With lower load

levels, the system will not start up correctly at low line because the OVP generated at start-

up lasts so long that the VCC voltage drops below the UVLO of the L6562 (e.g. with 4W load

the system would stop for 600 ms @ VIN = 90VAC). Load transients from the maximum load

to levels below 15W may cause the VCC to be lost as well. If supplying the L6562 with an

external source, the minimum load that can be handled properly drops to virtually zero.

AN1895 Datasheet(PDF) 11 Page - STMicroelectronics