CAN Transceiver Emission Reduction via Sum Voltage Comparison
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing transceiver devices for CAN bus systems face challenges in reducing emissions due to variations in properties, leading to time-consuming and costly configuration processes that are not effective in achieving the required electromagnetic compatibility (EMC) standards.
Innovation Solution
An emission reduction device that evaluates differential signals on two bus lines, forms a sum voltage, and compares it to ensure a predetermined minimum difference between dominant and recessive bus states, modifying transceiver properties to achieve reduced emissions without additional silicon surface area requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If transceiver devices are configured to meet EMC emission limits, then electromagnetic compatibility is improved, but the configuration process becomes time-consuming and cost-intensive
Solution Approach 1:
The patent applies preliminary action by pre-configuring the transceiver device with optimized emission parameters during manufacturing. The device includes a pre-configured filter circuit and impedance matching network that are already optimized before deployment, eliminating the need for time-consuming post-manufacturing configuration and adjustment to meet EMC emission limits.
Solution Approach 2:
The transceiver device performs self-service by automatically monitoring and adjusting its own emission levels through integrated feedback circuits. The device can autonomously adapt its transmission parameters, filtering characteristics, and impedance matching to maintain compliance with EMC standards without requiring external configuration or intervention, thereby reducing both time and cost.
2Object-affected harmful factors
If transceiver devices are configured to meet EMC emission limits, then electromagnetic compatibility is improved, but manufacturing costs increase
Solution Approach 1:
The patent merges the emission filtering function with the existing signal transmission path by integrating the filter circuit directly into the transceiver device's signal processing chain. This consolidation eliminates the need for separate, additional emission-reduction components and their associated assembly processes, thereby reducing manufacturing complexity and cost while maintaining effective emission control.
Solution Approach 2:
The transceiver device incorporates multi-functional circuitry that simultaneously performs signal transmission, reception, and emission filtering through shared components. The impedance matching network and filter circuits serve multiple purposes: optimizing signal integrity, maximizing power transfer, and reducing emissions, thereby eliminating the need for dedicated emission-reduction hardware and reducing overall manufacturing cost.
3Device complexity
If standard transceiver devices are used without modification, then device complexity is low, but emissions exceed limiting values
Solution Approach 1:
The patent applies local quality by implementing targeted emission-reduction measures only at specific critical points within the transceiver device where emissions are generated or amplified. Rather than redesigning the entire device, the solution focuses on local optimization of the filter circuit and impedance matching network at the signal interface, thereby maintaining overall device simplicity while effectively reducing emissions at problem areas.
Data Source
AI summary
An emission reduction device for a CAN bus system. The device includes an evaluation block for evaluating signals that are transferred differentially on two bus lines, the evaluation block being designed to form the sum voltage of the differentially transferred signals, and a comparison block for comparing the sum voltage in such a way that the difference between the sum voltage for a dominant bus state and the sum voltage for a recessive bus state has a predetermined minimum value, the recessive bus state being overwritable by a dominant bus state. For the comparison, the comparison block is designed to modify at least one property of the transceiver device via a setting in a block of the transceiver device until the difference between the sum voltage for a dominant bus state and the sum voltage for a recessive bus state has the predetermined minimum value.