The adapter provides stable AC power for the LED desk lamp of the scheme->AC-DC step-down conversion. Its real-time load output capability will affect the performance of the LED desk lamp of this scheme. It is used for the adapter of the 3X1W white LED desk lamp of this scheme. When the output current should be greater than 1A, the voltage should be stable at DC12V. Some adapters with poor load capacity, when connected to the LED light source load of this solution, its real-time output voltage will drop to 7V, or even 6.5V. For the LED driver IC whose working voltage starts from 8V, it will enter the under voltage protection state and stop. Work, once the driver IC stops working, the voltage rises back to 12V, and the LED driver IC enters the working state again, so that the LED desk lamp has a visible flash of light. At this time, only the replacement of the adapter with good load capacity can make the LED desk lamp work normally. At the same time, the LED driver IC with the working voltage range from 6V should be selected, which can also reduce the selection requirements of the adapter to reduce the production supporting cost.