DocID028405 Rev 1
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UM1955
LED driver configuration
28
6
LED driver configuration
The LED driver configuration allows users to drive an LED with a constant current. As
shown in
Figure 7
, when the forward voltage varies, the current and thus the light intensity is
highly variable.
Figure 7. Forward current vs. forward voltage
This is why it is recommended to control the LED by current, and thus this architecture is
useful.
6.1 Schematic
diagram
Figure 8
shows the circuit schematic of the LED driver configuration.
Figure 8. LED driver configuration circuit schematic
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