Current Generator Circuit With Dynamic Element Matching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current current generator circuits face challenges in generating an output current with a precise ratio to a reference current due to mismatch errors in electrical components, such as transistors, which are not exactly identical in size, leading to inaccuracies in current mirroring.
Innovation Solution
The proposed electric circuit arrangement employs dynamic element matching using a current generator circuit with controllable switching circuits, a random code generator, and a counter to dynamically re-group electrical components, generating pseudo-random codes to control the switching of output current paths, thereby reducing mismatch errors and achieving a precise output current ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If electrical components are manufactured with defined exact geometrical size to achieve precise current ratio, then manufacturing precision is improved, but mismatch error still occurs because components are not exactly identical
Solution Approach 1:
The patent applies dynamic element matching by making the connection configuration dynamic rather than static. The controllable switching circuits dynamically connect different electrical components to output terminals based on random codes, changing the active component configuration over time. This dynamic approach averages out mismatch errors across multiple components, achieving better current ratio accuracy than any single component could provide.
Solution Approach 2:
The system uses periodic action through clock signals to systematically cycle through different component configurations. The random code generator and controllable switching circuits operate in periodic cycles, sequentially activating different electrical components. This periodic switching ensures that over time, the output current represents an accurate average of multiple components, reducing the impact of individual component mismatches.
2Reliability
If dynamic element matching is implemented to reduce mismatch errors, then current ratio accuracy is improved, but device complexity increases due to additional switching circuits and control logic
Solution Approach 1:
The patent segments the current generation function across multiple parallel output current paths, each with its own electrical component and controllable switching circuit. Instead of using a single complex component or a simple sequential switching mechanism, the system divides the functionality into multiple independent segments that can operate in parallel. This segmentation allows the system to achieve high accuracy through statistical averaging while keeping each individual segment relatively simple.
Solution Approach 2:
The system incorporates a random code generator that automatically produces the control signals needed for dynamic element matching without requiring external intervention. The controllable switching circuits self-regulate their operation based on the generated random codes, and the overall system self-adjusts to maintain accurate current ratios. This self-service capability reduces the need for complex external control logic and simplifies the overall device architecture.
Data Source
Figure 1
Figure 2~4
Figure 5
AI summary
An electric circuit arrangement (10) to control current generation comprises a current generator circuit (100) comprising a plurality of output current paths (P1, ..., PN+1) and a plurality of controllable switching circuits (SC1, ..., SCN+1), wherein each of the output current paths (P1, ..., PN+1) includes a respective electrical component (T1, ..., TN+1) to define a current in the respective output current path (P1, ..., PN+1). The electric circuit arrangement (10) further comprises a random code generator (300) to provide a respective code derived from a respective one of the random codes, and a counter (400) to generate a count. A controller (200) is configured to use the respective derived code or the count to control a respective one of the controllable switching circuits (SC1, ..., SCN+1) of the current generator circuit (100).