Virtual-Channel A/D Conversion for Flexible Sensor Scan Order
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Microcontrol units for automobile engine control face challenges in converting analog signals from multiple sensors at higher speeds due to limitations in the number of analog-conversion terminals, restricting the order of A/D conversions and making it difficult to perform A/D conversions on analog signals from outside sources in an arbitrary order.
Innovation Solution
A semiconductor integrated circuit device with multiple analog ports, an A/D conversion part, and an A/D conversion control part that includes virtual channel registers and a scan-group-forming register, allowing for arbitrary ordering of A/D conversions by setting correspondences between virtual channels and analog ports, and controlling the A/D conversion process through start and end pointers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the number of analog-conversion terminals of a microcontrol unit is increased to handle more sensors, then the conversion speed and capacity improve, but the device complexity and cost increase
Solution Approach 1:
The patent implements a virtual channel mechanism where a single physical A/D converter can be assigned to multiple virtual channels, allowing one terminal to handle multiple sensor inputs through time-division multiplexing. This makes the A/D converter universal and multi-functional, capable of serving many sensors without increasing the physical terminal count.
Solution Approach 2:
The patent segments the A/D conversion process into multiple virtual channels (VC0-VC7) that can be independently configured and controlled. Each virtual channel represents a logical conversion path that can be assigned to different physical ports and scan groups, dividing the conversion task into manageable segments that can be executed sequentially.
2Ease of operation
If the conversion order is restricted to ascending order of terminal numbers, then the control logic is simplified, but the flexibility and adaptability of the system deteriorates
Solution Approach 1:
The patent introduces dynamic conversion order control through scan group configuration. Instead of fixed ascending order, the system allows users to define custom scan groups with specific start and end virtual channels, enabling flexible conversion sequences that adapt to different application requirements while maintaining manageable control logic.
Solution Approach 2:
The patent allows preliminary configuration of virtual channel assignments and scan group definitions before actual A/D conversion occurs. By pre-setting the conversion order and port assignments in registers, the system prepares the conversion sequence in advance, enabling flexible ordering without complicating the real-time control logic.
3Quantity of substance
If external multiplexers are added to expand analog input capacity, then the number of convertible signals increases, but the system complexity and external component requirements increase
Solution Approach 1:
The patent counteracts the need for external multiplexers by providing internal virtual channel multiplication. The virtual channel mechanism effectively weights the internal processing capacity to match or exceed the functionality of external multiplexer additions, eliminating the need for additional external components while maintaining signal conversion capacity.
Data Source
AI summary
The semiconductor integrated circuit device has: more than one analog port; an A/D conversion part operable to execute an A/D conversion process for converting an analog signal taken in through each analog port into a digital signal for each preset virtual channel; and an A/D conversion control part operable to control an action of the A/D conversion part. The A/D conversion control part includes: virtual channel registers on which correspondence between the virtual channel and the analog port can be set; and a scan-group-forming register on which a start position of a scan group and an end position thereof can be set. The A/D conversion control part controls the A/D conversion part to successively execute an A/D conversion process on a plurality of virtual channels from a virtual channel associated with the start pointer to a virtual channel associated with the end pointer.