ECM Driver Circuits Preventing Inrush Current Faults
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Engine control modules (ECMs) generate false fault codes due to high initial inrush currents in capacitive loads like Variable Geometry Turbocharger, which existing technologies fail to adequately address.
Innovation Solution
The ECM employs separate high side and low side driver circuits for multiple loads, with a common return pin, allowing only one load to be connected to the voltage source at a time, and using a microcontroller to manage the connection through specific driver circuits to prevent inrush current-induced faults.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If multiple loads share a common return pin and voltage source, then device complexity is reduced, but false fault codes are generated due to inrush current
Solution Approach 1:
The patent segments the common return pin connection by introducing separate low-side driver circuits for each load. Each driver circuit has its own dedicated return path to ground, effectively dividing the shared return connection into isolated segments. This segmentation prevents inrush current from one load from affecting the fault detection of another load, eliminating false fault codes while maintaining circuit organization.
Solution Approach 2:
The patent introduces intermediate low-side driver circuits as mediators between the loads and the ground connection. These driver circuits act as buffer elements that isolate the inrush current effects of capacitive loads from the main return path. The intermediaries control the timing and path of current flow, preventing direct inrush current from reaching the common return pin and causing false faults.
2Adaptability or versatility
If capacitive loads are connected to voltage source, then system functionality is achieved, but high inrush current is generated causing false faults
Solution Approach 1:
The patent implements preliminary action by using the microcontroller to predict and prepare for inrush current conditions before they occur. The system monitors load connection requests and proactively controls the timing of power delivery, preparing the driver circuits to manage inrush current effects before the actual current surge happens. This preliminary control prevents false fault codes from being generated.
Solution Approach 2:
The patent employs feedback mechanisms where the microcontroller continuously monitors the status of each load connection and adjusts the operation of high-side and low-side driver circuits accordingly. When a capacitive load is detected or requested, the feedback system modifies the power delivery timing and magnitude to limit inrush current. This closed-loop control ensures compatible operation with various load types while preventing harmful inrush current effects.
Data Source
AI summary
Methods and apparatuses for connecting multiple loads with a common return pin in engine control module application are disclosed. Only one of the multiple loads can be connected to a power source at a time. At the high side, each load is coupled to the power source through a respective pin at a connector. At the low side, the multiple loads share a common return pin at the connector that connects the loads to the ground. When a first load is connected to the power source at the high side, a first low side driver circuit is used to connect the first load to the ground at the low side. When a second load is connected to the power source at the high side, the second low side driver circuit is used to connect the second load to the ground at the low side.