This detection resistance value is usually very small, only a few tenths of a ohm, if you want to install a few tenths of a ohm potentiometer on the wall to adjust the current is not possible, because the lead resistance will also be a few tenths of a ohm. So some LED chips provide a control voltage interface, change the input control voltage can change its output constant current value. The problem with using forward current to adjust brightness is that it also changes the spectrum and color temperature. Because white LED is generated by using blue LED to stimulate yellow phosphor, when the forward current decreases, the brightness of blue LED increases while the thickness of yellow phosphor does not decrease proportionally, so that the main wavelength of its spectrum increases.

Common-Cathode CC 3022AGG 7-Segment digit 3022AGG LED Common-Anode CA 3022BGG Display 3022BGG 0.30 inch
Common-Cathode CC 3202AGG 7-Segment digit 3202AGG LED Common-Anode CA 3202BGG Display 3202BGG 0.30 inch

The light source with Ra 100 value
The standby LED lighting of emergency
LED light source index and average life
LED incandescent lamp color response
Color performance of LED light source
Color temperature LED source irradiation
Change the brightness of the LED
LED chips provide control voltage interface
In the RGB LED system
LED supply voltage and load voltage