Choosing an implementation strategy

AN1756

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Choosing an implementation strategy

In order to have a centralized control of each dimmable ballast of a room, a communication

protocol is needed. DALI is an economic solution that is more and more widely possibility

becoming popular in the lighting market. To find out the benefits of DALI, please refer to

document 3 referenced in Section 4

Since DALI is a digital protocol, it needs to handled by a microcontroller like ST7DALIF2.

Various topologies can be used to integrate this digital communication. It can work together

with a ballast controller, just for DALI communication as shown in Figure 3:

Figure 3.

Micro handles only communication

or it can do the DALI communication and take the place of the driver control, like in Figure 4:

Figure 4.

Micro handles communication AND control

The choice is up to the designer. Whatever solution is chosen, ST is the first semiconductor

manufacturer able to provide both the right high-voltage driver or controller, as well as a

microcontroller with an on-chip decoder for the DALI protocol.

To get more information on the first topology and its advantages, please refer to application

note AN1900 “Hardware Implementation for ST7DALI-EVAL” or order the ST7DALI-EVAL

evaluation kit.