Future E/E architectures used for autonomous driving applications must continually monitor the voltages and currents for loads connected to the powernet. The central compute modules use this information to determine the state of health of the loads and to provide early warning of a potential malfunction, allowing fail-operational system performance.

Remote Control Protocols (RCP) over Automotive Ethernet allow the central compute modules to monitor the loads via 10BASE-T1S, 100BASE-T1 or other connections, removing the need for application software in the end node. This dramatically reduces software development time and complexity, and removes dependencies on specific microcontroller platforms, enabling multi-sourced reuse.

We will show how central compute modules can use dedicated remote control protocol IC’s or pre-programmed microcontrollers to control local hardware to measure voltages and currents in loads connected to the powernet without the need for any software in the electronic control unit (ECU) driving that load.
We first review an industry-standard SmartFET showing how both a comparator with a reference and an external analog-to-digital converter can measure the current and voltages on the load. We then show how the connections for these loads can be multiplexed together to be connected to the microcontroller or a remote control protocol device. Using the example we will show what commands can be sent from the central compute to the remote control protocol device to implement the required monitoring, comparing the comparator based approach with the analog-to-digital converter approach.

We will review the design and performance of a specific implementation using a dedicated remote control protocol device.