In part one of this blog series I introduced a new solution for the illumination of streets in big cities that is based on the adoption of LED lights, a smart solution in terms of efficiency and cost-reduction.
- In conjunction with a smart power supply, LED street lamps become intelligent devices. They gradually increase their brightness as daylight fades and automatically reduce their brightness as the sun rises. They communicate with the smart grid and pave the way to the smart cities.
The STMicroelectronics Company is expanding its portfolio in the field of electronics for smart grid systems, has produced a new solution (see Figure 1) to manage LEDs that are dimmable and can be driven by a microcontroller, in order to reduce power consumption and realize a really smart system of management of electricity, avoiding losses. These losses may be caused by commonly utilized lights, bulbs that create a waste of energy, or by a non-optimized management of power.
This new solution is available in a demo board that is based on the digital power controller STLUX385A, a controller able to drive a row of LEDS for smart-lighting applications by mean of a proprietary power conversion protocol. The core of the new ST system for the smart driving of a row of LEDs is the DALI:
- DALI (digital addressable lighting interface), standardized as IEC 929, is the new interface for lighting control solutions defined by the lighting industry. The DALI protocol is generally implemented in a DALI communication module (DCM): a serial communication circuit designed for controllable electronic ballasts. “Ballast” is a device or circuit used to provide the required starting voltage and operating current for LED.
When speaking of LEDs it’s important to keep in mind that the LED devices have to be supplied at a constant electric current, and the LED starts emitting light once the forward voltage electric threshold is reached. The electric power supplied to the LED, which is the product of the voltage and of the current applied to the LED, has to be absolutely constant and stable in time to guarantee the effectiveness of LED illumination.
In the next and final part of this blog series, more solutions from big semiconductors companies are described. Did you ever work on a LED-based smart illumination system? What types of functionality would you add to this smart system?