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LED setting parameters
Parameters
Description
Led Vo
Voltage of operating point
Led Io
Current of operating point
Led Rf
Coefficient Coeff
Io is given by LED Driver, if there is an error between the actual output and the set value,
the corresponding load value Vo will be different. For example, if Io is set to 1A and the
actual output current of the power supply is 1.1A, the actual output voltage value will also
be higher. It is normal for a slight deviation to the output voltage. The specific formula is as
follows:
The actual load-value is loaded according to the following formula:
Vx = (1 − Coeff) × Vo + Ix × Coeff ×
Vo
Io
;
Vx:The output voltage of the LED driver under actual load adjustment.
Ix:The output current of the LED driver under actual load adjustment.
Set different Vo, Io and Rf, the calculation above will bring different data.
Figure 3.26 LED mode testing page
Parameter calculation:
The users need to set Vo, Io, Rf in LED mode.
Vo, Io can be obtained from the parameters described the LED characteristic. The real
load is usually a LED string (n pieces LED in series). Vo should be set to n times the
single-section parameter. It can also be set to any value in the LED driver output voltage
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