Solid-state shunt keeps LED strings working after single-device failure

For LED lighting applications that require high dependability, the NUD4700 from ON Semiconductor protects the LEDs in a string against transients and surge conditions in the event of open-circuit failure of one device in the string.

The device can also be used with other types of loads requiring circuit continuity. The NUD4700 is a two-terminal shunt that can be added at low cost and optimised for use with 1W LEDs operating at 350mA nominal current. Typical on-state voltage of 1.0V minimises losses when the shunt is active. The NUD4700 is also capable of resetting if the LED heals itself or is replaced.

 

FEATURES <250µA off-state current 2mm x 2mm x 1mm POWERMITE® package 35mA typical latching current 7.5V breakdown voltage

APPLICATIONS Non-maintainable LED light engines LED headlights LEDs with high-reliability requirements Crowbar protection for open-circuit conditions Over-voltage protection for sensitive circuits

 

 

On Semiconductor / NUD4700