Rohm rolls automotive headlight LED drivers

March 16, 2011 // By Christoph Hammerschmidt
Rohm Semiconductor has introduced a family of LED driver chips aiming at automotive high-brightness headlights. The devices integrate driver functionality for high and low beam as well as for daytime running lights in one package.

The BD838EFV-M LED drivers contain a buck/boost converter which ensures stable operation across a large voltage range of 5 to 30 V. In addition, this converter does away with the limitation with regard to the number of LEDs connected in series. Thus, designers now do not need to employ different driver devices for each different headlight LED function which simplifies design complexity and helps to reduce the number of external components.

Integrated protection mechanisms monitor voltage, supply current and temperature. A fault detection function for open and short circuit is also integrated. Brightness can be controlled trough linear or PWM controls, enabling designers to implement advanced dimming functions just by adding an RC combination. This RC circuit also helps to limit output voltage in the case of LED overheating. It is also possible to employ the BD838EFV-M without additional microcontroller.

The BD838EFV-M comes in an HTSSOP-28 package. Samples are available; OEM volumes will be available beginning May 2011.

For more information, visit www.rohm.com/eu