Serial Bus Node Wake-Up Module for Automotive Current Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current serial data bus systems in automotive applications face high current consumption when nodes repeatedly wake up for supervision functions, especially when the engine is stopped, leading to increased costs and complexity due to high network traffic and the need for multiple master nodes to wake slave nodes selectively.
Innovation Solution
A serial data bus communication system with a wake-up module in each node that uses a CAN bus interface module with a CAN data detector and timer to selectively wake up nodes based on specific IDs, allowing multiple master nodes and multicast functionality while minimizing complexity and current consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If nodes are repeatedly woken up for supervision functions, then system reliability is improved, but current consumption increases
Solution Approach 1:
The system performs preliminary actions by having master nodes send wake-up signals with identification fields before slave nodes need to be fully activated. This allows slave nodes to remain in low-power standby mode while still being prepared for selective activation based on the wake-up signal content, thus maintaining reliability through periodic supervision while reducing current consumption.
2Adaptability or versatility
If multiple master nodes are implemented to wake slave nodes selectively, then adaptability is improved, but device complexity increases
Solution Approach 1:
The system segments the wake-up function by assigning different identification fields to different master nodes and configuring slave nodes to respond only to specific IDs. This segmentation allows selective wake-up without requiring complex centralized control, as each node independently processes wake-up signals based on its configured ID list, thereby improving adaptability while managing complexity.
Solution Approach 2:
The identification field in the wake-up signal acts as an intermediary that carries information about which slave nodes should be activated. Instead of complex direct addressing or control logic, the ID field mediates the wake-up process by matching against configured IDs in slave nodes, enabling selective activation with simple comparison logic and reducing overall network complexity.
3Use of energy by moving object
If wake-up triggers are added to all nodes, then current consumption is reduced, but device complexity increases
Solution Approach 1:
Each slave node is equipped with a wake-up trigger that operates autonomously by comparing the identification field in incoming wake-up signals against its own configured ID list. This self-service mechanism allows nodes to independently determine when to wake up without external control logic, reducing current consumption through selective activation while keeping individual node complexity low through simple comparison operations.
Data Source
AI summary
A method of communication comprising sending communication signals switched between dominant and recessive values at clock intervals in frames over a serial data bus from at least one of a plurality of sending nodes to a plurality of receiving nodes. The receiving nodes have an operational state and a standby state in which the current consumption of the node is reduced compared to the operational state. The receiving nodes include wake-up trigger means for triggering transition from the standby state to the operational state in response to the communication signals. The frames of the transmitted signals include an identifier field during which the communication signal alternates between the dominant and recessive values in successive clock intervals with at least one significant occurrence during which the communication signal remains at one of the dominant and recessive values during at least two successive clock intervals, and the trigger means is selectively responsive to the position of the occurrence within the identifier field for triggering the transition from the standby state to the operational state.