Power Converter Switch Testing with Bias-Current Shunting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for testing switches in switched-capacitor circuits face challenges in accurately measuring resistance (RDSON) and leakage current due to interference from biasing currents, which can lead to faulty power converters being deployed.
Innovation Solution
A switching network with floating-regulators and shunts that divert biasing currents during measurement, allowing for precise determination of RDSON and leakage current without interfering with the measurement process, and a controller that manages these currents to ensure accurate testing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If biasing current is provided to floating-regulators to power drivers during normal operation, then switches can be properly driven and controlled, but measurement of electrical parameters (RDSON and leakage current) becomes inaccurate due to current interference
Solution Approach 1:
The current path is segmented into separate measurement and biasing paths using a shunt component. During measurement, the shunt directs current exclusively through the switch under test, isolating it from biasing currents. During normal operation, the shunt is bypassed and biasing currents flow through the floating-regulator to power drivers. This segmentation allows both reliable switch operation and accurate electrical parameter measurement without mutual interference.
Solution Approach 2:
The shunt's connection state is dynamically changed between measurement mode and normal operation mode. A controller selectively connects or disconnects the shunt based on the operational phase: connected during measurement to divert biasing currents, and disconnected during normal operation to allow biasing currents to power drivers. This dynamic reconfiguration resolves the contradiction between reliable operation and accurate measurement.
2Ease of operation
If biasing current flows through the switching network during testing, then drivers remain powered and switches remain controllable, but it interferes with and corrupts measurement data of RDSON and leakage current
Solution Approach 1:
The biasing current is extracted and removed from the measurement path during testing by routing it through the shunt to a separate return path. This extraction ensures that biasing currents do not contaminate measurement data while drivers remain powered through the floating-regulator. During normal operation, the biasing current is restored to the original path, maintaining ease of operation.
3Device complexity
If traditional testing methods are used without current diversion, then the testing process is simple and direct, but measurement accuracy deteriorates due to biasing current interference
Solution Approach 1:
The shunt acts as an intermediary component that mediates between the biasing current path and the measurement path. It provides a controlled route for biasing currents during measurement, preventing them from interfering with electrical parameter measurements while maintaining the overall simplicity of the testing process. The controller manages the shunt's connection state, automating the process without significant complexity increase.
Data Source
AI summary
A switching network includes a switch, a driver for the switch, and a floating-regulator that powers the driver. The floating-regulator includes a shunt that is used only when testing the network. The shunt diverts biasing current so that it does not interfere with a measurement of an electrical property of a switch.