LEDs are finding an increasing use in automotive and industrial lighting applications replacing incandescent bulbs. Compared to traditional bulbs, LED lighting improves power efficiency while delivering a similar rated light output. Consequently, LEDs are now being used in headlamps, rear lighting, interior lighting, and indicator lighting. In these applications, Smart High Side Switches can be used to drive LED strings or to provide power to standalone LED driver modules. The Smart High Side Switch should be chosen based on the functionality needed, primarily considering protection, diagnostics, and load current requirements. The Smart High Side Switch must be able to drive the LED DC current load as well as manage the challenges posed by the input capacitance and parasitic resistance of lighting modules.

In this section we will discuss the various LED load driving application types. We will dive into the load characteristics and how they impact the choice of the appropriate Smart High Side Switch. Two important diagnostic features for LED loads will be highlighted: load current sensing and open load detection. These two features offer improved functionality to improve reliability and provide feedback to enable simpler system maintenance. We will also discuss the ability to set an adjustable low current limit threshold since LED loads typically have lower maximum DC current compared to other common load types. This adjustable current limit improves short circuit protection, protects against slow current creeping, and lowers the cost of cables and connectors. Finally, we will discuss how to use this information to select the appropriate Smart High Side Switch.