Blocking Switch Control Pin Sharing for Voltage Sensing and Fast Discharge
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing controllers for power converters require multiple pins for controlling and detecting the voltage at the output terminal of a blocking switch, which hinders size reduction efforts.
Innovation Solution
A controller that uses a single control pin to detect the voltage at the output terminal of a blocking switch and perform switching operations, incorporating a sensing circuit with a control switch, variable resistance circuit, and judgment circuit to manage detection resistance and provide a notification signal for switching, thereby reducing the number of pins and controller size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate control pin and detection pin are used for blocking switch control and voltage detection, then control reliability is improved, but pin count and controller size increase
Solution Approach 1:
The patent combines the control pin and detection pin into a single integrated pin that performs both control and voltage detection functions. The controller uses this single pin to both control the blocking switch and detect the output terminal voltage, thereby reducing the total pin count and controller size while maintaining the necessary control and detection capabilities through functional integration
Solution Approach 2:
The single control pin is designed to serve multiple functions: it acts as both a control signal output terminal for the blocking switch and a voltage detection terminal for monitoring the output terminal voltage. This multi-functional design allows the same pin to perform different roles at different times or simultaneously, reducing the overall pin requirement without sacrificing control reliability or detection accuracy
2Measurement precision
If high resistance value is used during voltage detection, then detection precision is improved, but discharge speed of output terminal voltage decreases
Solution Approach 1:
The patent employs a variable resistance circuit that dynamically adjusts its resistance value based on the operational state of the blocking switch. During voltage detection when the switch is off, the circuit uses a high resistance value to ensure accurate voltage measurement. When the switch needs to be discharged or turned on, the resistance value is reduced to accelerate the discharge process. This dynamic adjustment allows the system to optimize both detection precision and discharge speed at different operational stages
Solution Approach 2:
The controller periodically switches between different resistance values in the variable resistance circuit based on the operational requirements. During detection phases, high resistance is applied for precision measurement; during discharge phases, low resistance is applied for rapid voltage reduction. This periodic switching between resistance states enables the system to achieve both high detection precision and fast discharge performance through time-dependent resistance modulation
Data Source
AI summary
A controller for controlling a blocking switch of a power converter is provided. The controller includes a control pin and a sensing circuit. The control pin is coupled to a control terminal of the blocking switch and an output terminal of the blocking switch. The sensing circuit includes a control switch, a variable resistance circuit, and a judgment circuit. A first terminal of the control switch is coupled to the control pin. The variable resistance circuit is coupled between a second terminal of the control switch and a reference low voltage. The judgment circuit controls the variable resistance circuit to provide a detection resistance value with a minimum value, and turns on the control switch to obtain a sensing voltage value. When the detection resistance value has a maximum value and the sensing voltage value is lower than a reference voltage value, the judgment circuit provides a notification signal.