AN4382 Datasheet, PDF (59/70 Pages) STMicroelectronics – 100 W LED street lighting application using STLUX385A

AN4382
User interface
9.5
0 - 10 V interface
The 0 - 10 V interfaces can be enabled using the “in” command described in Section 9.3 on
page 46. By default, the STEVAL385LEDPSR demonstration board is shipped with the
0 - 10 V interface disabled. The 0 - 10 V and DALI interfaces are mutually exclusive.
The 0 - 10 V reference signal can be generated via a 0 - 10 V generator. Alternatively, it is
possible to simulate the signal using a potentiometer. The correct value of this
potentiometer is 110 KΩ, which can be obtained using two potentiometers in series: 10 KΩ
plus 100 KΩ. The 100 KΩ potentiometer shall be used when the output voltage is over 5 V,
while the 10 KΩ potentiometer can be used when the output voltage is below 5 V.
The power necessary to read the input voltage is automatically generated by the
STEVAL385LEDPSR demonstration board. This solution provides excellent insulation and
all the features of the demonstration board. The maximum 0 - 10 V interface input voltage
accepted on this is 15 V.
The on/off transaction is regulated via a hysteresis mechanism. LEDs are switched off when
the 0 - 10 V interface reaches V < 1 V. LEDs are switched on when V > 1.25 V.
The relationship between the voltage applied to the 0 - 10 V interfaces and the LED output
current is defined in Table 21.
Table 21. 0 - 10 V voltage to output current
Voltage applied to connector J9
Output current (1 A scale)
Output current (500 mA scale)
More than 10 V and less then 15 V
1A
10 V
1A
500 mA
500 mA
9V
900 mA
450 mA
8V
800 mA
400 mA
7V
700 mA
350 mA
6V
600 mA
300 mA
5V
500 mA
250 mA
4V
400 mA
200 mA
3V
300 mA
150 mA
2V
200 mA
100 mA
1V
100 mA
50 mA
Below 1 V
Off
Off
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