Interfacing Microcontroller with High-Side Switch

In this circuit, both channels can be controlled individually by external/internal clock signals or by direct inputs. Using the internal clock allows fully autonomous device operation. Programmable output voltage slew rates (individually programmable) help improve EMC performance. To avoid shutting off the device during inrush current, while still being able to closely track the load current, a dynamic overcurrent threshold profile is featured. Switching current of each channel can be sensed with a programmable sensing ratio. Whenever communication with the external microcontroller is lost, the device enters a fail-safe operation mode, but remains operational, controllable, and protected. This device is powered using SMARTMOS technology.

This high-side switch has been designed for truck, bus, and industrial applications. The low RDS(on) channels (<6.0 mOhm) can control different load types; bulbs, solenoids, or DC motors. Control, device configuration, and diagnostics are performed through a 16-bit serial peripheral interface (SPI), allowing easy integration into existing applications.