Power Switching Device Short Circuit Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power switching devices can suffer damage due to sudden voltage drops when the output node is connected to ground, caused by large currents passing through the switching device, leading to potential short circuits.
Innovation Solution
A power switching device incorporating a current limiting circuit and a short protection circuit to detect and manage excessive currents and voltage drops, using comparators and set circuits to control the switching of the transmitting switch, ensuring it turns off during short circuits or high currents to prevent damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the transmitting switch is used to transmit input voltage to the output node, then the power transmission function is achieved, but when the output node is connected to ground, large current causes damage to the switch and coupled elements
Solution Approach 1:
The short protection circuit performs preliminary detection of output node voltage and generates a protection signal before the large current can cause damage. When the output node voltage drops to a low level (indicating potential ground connection), the circuit proactively turns off the transmitting switch, preventing the harmful large current from flowing and thus protecting the switch and coupled elements from damage.
Solution Approach 2:
The short protection circuit continuously monitors the output node voltage and uses this feedback information to control the transmitting switch state. The voltage detection result is fed back to the control logic, which adjusts the switch state accordingly - keeping it on during normal operation and turning it off when voltage drop indicates a short circuit condition, thereby maintaining reliability while enabling power transmission.
2Reliability
If the current limiting circuit turns off the transmitting switch when current exceeds a predetermined value, then the switch and elements are protected from damage, but the power transmission is interrupted
Solution Approach 1:
The current limiting circuit continuously monitors the current through the transmitting switch and uses feedback control to manage the switch state. When current exceeds the predetermined threshold, the feedback signal triggers the switch to turn off, providing protection. When current returns to normal levels, the feedback signal allows the switch to resume operation, thus protecting the system while minimizing interruption to power transmission productivity.
Solution Approach 2:
The current limiting circuit enables the transmitting switch to quickly skip from the on state to the off state when overcurrent is detected, and rapidly return to the on state once the condition is resolved. This rapid switching minimizes the duration of power transmission interruption while ensuring adequate protection, allowing the system to rush through the protective action with minimal impact on overall productivity.
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
The solution effectively prevents damage by limiting current and detecting short circuits, maintaining the output voltage and preventing sudden drops, thus enhancing the reliability and efficiency of the power switching device.
Implementation Method 1
The first comparator compares a voltage of the output node and a first reference voltage to generate a first comparison result to turn off the first transmitting switch
Implementation Method 2
The current limiting circuit is coupled to the first transmitting switch to detect a current passing through the first transmitting switch
Implementation Method 3
The first set circuit receives the voltage of the output node and generates the first reference voltage according to the voltage of the output node
Data Source
AI summary
A power switching device is provided. A first transmitting switch transmits an input voltage to an output node when the first transmitting switch is turned on. When the current passing through the first transmitting switch exceeds a predetermined value, a current limiting circuit turns off the first transmitting switch. When a short circuit occurs between the output node and a ground node, a short protection circuit turns off the first transmitting switch. The short protection circuit includes a first comparator and a first set circuit. The first comparator compares a voltage of the output node and a first reference voltage to generate a first comparison result to turn off the first transmitting switch. The first set circuit generates the first reference voltage according to the voltage of the output node. The first reference voltage is less than the voltage of the output node.