OSRAM OPTOTRONIC Constant current LED power supplies with 3DIM User Manual

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3.2.2. Light sensor application

3.2.2.1. Using OSRAM DIM MICO/PICO

Daylight compensation can be easily obtained with the

LEDset interface by connecting existing commercial light

sensors (only plug-and-play sensors as described in the

DIM MICO/PICO is a light sensor from OSRAM which is

compatible with 1…10 V interfaces. The sensor works once

it is connected directly between Vset and GNDset.

This sensor is used to monitor, measure and maintain the

brightness level of its detection area to a preset value, which

is adjustable by a setpoint potentiometer screw. Once the

daylight decreases and the brightness of the area reaches or

falls below the preset value, the sensor starts to increase its

impedance between Vset and GNDset, thus increasing the

Vset voltage level. The higher current demand to the LEDset

ECG results in an artifi cial light compensation by the light of

the LED module.

Note: The 274 µA of Iset are enough to supply the sensor.

Particular attention should be paid to presetting the bright-

ness setpoint of the sensor, referring to the setup procedures

described in the DIM MICO/PICO datasheet. In any case,

Vset should be in the range of 10 to 11 V at the desired

maximum current output (no daylight present) to avoid

reaching the turn-off range of the LEDset interface charac-

teristic (see fi gure 4).

This warning does not apply if a LEDset ECG is used in

combination with a current set (CS) confi guration. For more

details, please see chapter 3.2.2.3. General notes on local

dimming: LEDset and “current set” combination.

For more detailed information about DIM MICO/PICO,

please refer to www.osram.com/lms-sensors

following chapter). Light sensing can be approached by

using standard 1…10 V-compatible light sensors or by devel-

oping light sensors from IC chips and converting their output

signal to the Vset range of the LEDset interface.

LEDset APPLICATIONS

Figure 9: Local dimming – light sensor application with DIM MICO/PICO.