Transient Voltage Suppressor Circuit for eFuse Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies lack an efficient method to determine the transient voltage and current ratings of electronic fuses (eFuses) under transient fault conditions, which is crucial for ensuring their ability to protect downstream loads during overloads or short circuits.
Innovation Solution
A test circuit is designed to simulate transient fault conditions by discharging an inductor through a device under test (DUT), such as an eFuse, and measuring its response during a controlled DUT avalanche interval. The circuit includes switches to control the discharge path and a TVS to clamp the voltage after the avalanche interval.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If an inductor is discharged through the DUT to simulate transient fault conditions, then the transient voltage and current ratings can be determined, but the DUT may sustain damage during the testing process
Solution Approach 1:
The patent applies preliminary action by pre-charging the inductor before the test sequence. The controller charges the inductor to a predetermined energy level before initiating the transient fault condition simulation, ensuring that the DUT is subjected to controlled and predictable current spikes. This preliminary preparation allows precise control over the stress applied to the DUT during testing.
Solution Approach 2:
The patent uses an intermediary approach by introducing a parallel discharge path that includes a switch and resistor. During the transient fault condition simulation, when the test switch opens, the inductor current can divert through this parallel path (switch and resistor in series) instead of all current flowing through the DUT. This intermediary path acts as a current分流 (current division) mechanism that reduces the stress on the DUT while still allowing the test to proceed.
2Productivity
If the first switch is opened to discharge the inductor through the DUT, then transient fault conditions are applied for testing, but the voltage across the DUT may exceed its avalanche rating
Solution Approach 1:
The patent employs an intermediary voltage regulation mechanism by introducing a parallel discharge path with a switch and resistor. When the test switch opens and the inductor discharges, the voltage across the DUT is regulated by this parallel path. The resistor in the parallel path acts as a voltage limiter, preventing the voltage from exceeding the DUT's avalanche rating while still allowing sufficient current to flow for effective testing.
Solution Approach 2:
The patent applies parameter changes by dynamically adjusting the circuit configuration through switch control. The controller changes the state of the first switch and second switch to transition between different circuit topologies: during normal operation, the circuit allows standard current flow; during testing, it creates a controlled discharge path. This dynamic parameter adjustment enables the system to apply transient fault conditions while maintaining voltage within safe limits.
3Reliability
If the second switch is closed to divert current from the inductor to the TVS, then the voltage across the DUT is clamped, but the testing process becomes more complex
Solution Approach 1:
The patent uses an intermediary voltage clamping mechanism by introducing a TVS (transient voltage suppressor) in parallel with the DUT, controlled by a second switch. When the second switch closes, the TVS activates and clamps the voltage across the DUT to a safe level. This intermediary voltage regulation component protects the DUT during transient fault conditions while maintaining a relatively simple circuit structure compared to more complex active regulation systems.
Solution Approach 2:
The patent employs a cost-effective protection approach by using a TVS (transient voltage suppressor) that is designed to handle transient voltage spikes. The TVS acts as a sacrificial protection element that clamps voltage during transient faults, protecting the expensive DUT from damage. This approach uses a relatively simple and cost-effective protection mechanism rather than complex active regulation systems.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method allows for precise determination of the transient voltage and current ratings of eFuses, ensuring they can effectively protect against transient faults without sustaining damage, thereby enhancing the reliability and safety of electronic circuits.
Implementation Method 1
An inductor is coupled to a first switch. The first switch is coupled to a second switch. The circuit includes a test module coupled to the first switch and the second switch. The test module includes a DUT.
Implementation Method 2
A TVS (transient voltage suppressor) is coupled to the second switch. The TVS being coupled to the second switch, wherein the energy from the inductor is diverted to the TVS responsive to the tolling of the DUT avalanche interval.
Data Source
AI summary
A circuit for testing a DUT (device under test) includes an inductor coupled to a first switch, and the first switch is coupled to a second switch. The circuit includes a test module coupled to the first switch and the second switch. The test module includes a DUT. The circuit also includes a TVS (transient voltage suppressor) coupled to the second switch.