New-Tech Europe | March 2017 | Digital Edition

Automotive Special Edition

features, such as undervoltage lockout (UVLO), overvoltage lockout (OVLO) and output overvoltage protection (OOVP) can be executed by processing the sensed input and output voltage. This ensures that the LED driver is operating within desired specifications and the LED is protected from abnormal input and output conditions. The CPU can also process the thermal data from a sensor to implement a LED’s thermal management. Moreover, when setting the dimming level of the LED driver, the CPU can process triggers from a simple external switch or command from a serial communication. Also, the parameters of LED driver can be sent to external devices through the serial communication for monitoring or testing. Aside from the features mentioned above, the designer has the luxury to add more intelligence on their own LED application inclusive of communications, like DALI or DMX, and control customizations. Figure 4 shows an example of a complete switched-mode dimmable LED driver solution using the LED dimming engine. Conclusion A LED dimming engine can be used to create an effective switched- mode dimmable LED driver. The effectivity equates on its capabilities to drive multiple LED strings, to provide efficient energy source, to ensure LED’s optimal performance, to maintain a long life for the LEDs and to add intelligence in the system.

Figure 3. LED dimming waveform

Figure 4. Switched-mode dimmable LED driver solution

significant bandwidth to execute

other important tasks. Protection

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