Until now LED Headlight bulbs have relied on passive thermal management systems such as large heat sinks, metal ribbons, or loud cooling fans. These methods can be unreliable and almost always make the installation process more difficult and time consuming for the installer.
ORACLE Lighting’s new V-Series bulbs feature our SmartDrive™ Active Thermal Regulation (ATR) temperature management. The integrated constant current linear LED driver inside the bulb uses a system called “thermal foldback” to protect the LEDs and the bulb components.
The LED driver operates from a 6V to 24V input and offers constant current output at up to 1 Amp. If the bulb becomes hot and surpasses optimal working temperature, the driver can reduce the current by altering the PWM duty cycle until temperature stabilizes.
Supplementing passive thermal management with active techniques such as this allow for a very small bulb package without risking damage to the LED or creating an environment where the LED lifetime would otherwise be significantly shortened.
Although reducing the current reduces luminosity, the current reduction is minimal and such that the change in luminosity is below the threshold that a consumer can detect. Fortunately, the human eye is poor at detecting luminosity changes in high-brightness devices so there is reasonable flexibility in the balance between controlling temperature and noticeably compromising luminosity.