OSRAM OPTOTRONIC Constant current LED power supplies with 3DIM - Manual (Page 7)

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LEDset SPECIFICATIONS
2.2. LEDset characteristic
2.2.1. General description
With the LEDset interface, the output current can be defi ned
relative to the maximum nominal output current of the control
gear.
The basic relationship between the LEDset voltage (Vset)
and the ECG output current (Iout) is defi ned by the following
equation:
where Inom
max
is the maximum nominal output current of
the ECG and Vset voltage is the voltage between Vset and
GNDset.
The relationship is valid for values of Iout that are within
the current range of the control gear, i.e. between Imin
and Inom
max
.
The generic Iout versus the Vset characteristic is shown in
fi gure 3.
Figure 3: Generic Iout vs. Vset characteristic.
Designation of lines:
Blue line: Ideal case
Orange line: Typical real ECG behavior with Imin
limitation and no turn-off capability
Table 1: LED output current as function of Vset.
0 < Vset < Vmin Iout = lmin or lout = 0 (see chapter 2.2.2. for details)
Vmin < Vset < 10 V Iout according to LEDset relationship
10 V < Vset < 11 V Iout = Inom
max
11 V < Vset < +12 Vset (or Vset, open) Iout = Imin (i.e. Iout = 0 if the ECG has a turn-off capability)
Iout Inom
max
( Vset 1 )
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