H-Bridge Buck-Boost Current Detection Across Buck and Boost Phases
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current buck-boost circuits face challenges in accurately detecting inductor current due to high costs and latency issues with traditional current sensors, limiting their application range and increasing the risk of damage during overcurrent protection.
Innovation Solution
A voltage conversion circuit utilizing a detection circuit with first and second detection resistors, which samples voltages across these resistors to output a current detection signal, allowing real-time inductor current detection regardless of buck or boost conversion phases, thereby reducing costs and latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a current sensor (Hall element) is added to detect inductor current, then measurement precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent introduces detection resistors as intermediary elements to convert inductor current into detectable voltage signals. Instead of directly measuring current with a complex sensor, the circuit uses simple resistors (R1, R2) to create voltage drops proportional to current, which are then amplified and processed by operational amplifiers to achieve accurate current detection without requiring expensive Hall elements.
Solution Approach 2:
The patent replaces the mechanical/magnetic Hall effect sensing mechanism with an electrical voltage division and amplification system. By substituting the Hall element's magnetic field detection with resistor-based voltage measurement and operational amplifier signal processing, the system achieves current detection through purely electrical means, reducing complexity and cost.
2Measurement precision
If a current sensor (Hall element) is added to detect inductor current, then measurement precision is improved, but loss of time increases
Solution Approach 1:
The detection resistors R1 and R2 continuously convert inductor current into voltage signals during all operating phases (buck conversion and boost conversion). The operational amplifiers continuously process these signals, providing uninterrupted real-time current detection information to the control unit, thereby eliminating detection latency and enabling immediate response to current changes.
Solution Approach 2:
The detection resistors are positioned in the current path beforehand to preemptively convert current into voltage signals. This preliminary conversion allows the control unit to receive current information in advance, enabling proactive control decisions and overcurrent protection before damage occurs, rather than reacting after a delay.
3Device complexity
If detection resistors are used instead of current sensors, then device complexity is reduced, but measurement precision deteriorates
Solution Approach 1:
The patent combines multiple functional elements into an integrated detection system: detection resistors for signal generation, operational amplifiers for signal conditioning and amplification, and a control unit for processing. This merging of functions compensates for the simplicity of individual components, achieving high measurement precision through the coordinated operation of the entire detection circuit rather than relying on a single complex sensor.
Solution Approach 2:
The patent optimizes detection parameters including resistor values (R1, R2), operational amplifier gain settings, and filtering characteristics to maximize measurement precision. By carefully selecting and adjusting these parameters, the system achieves accurate current detection using simple resistive elements and analog signal processing, matching or exceeding the performance of complex current sensors.
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 proposed solution enables accurate and cost-effective real-time inductor current detection, improving the safety and efficiency of buck-boost circuits by reducing detection latency and operational costs.
Implementation Method 1
The detection circuit may separately perform voltage sampling on a first resistor voltage of the first detection resistor and a second resistor voltage of the second detection resistor
Data Source
AI summary
This application discloses a voltage conversion circuit, a voltage converter, and an electronic device. The voltage conversion circuit mainly includes a detection circuit having a first detection resistor and a second detection resistor, and a buck-boost circuit of an H-bridge structure. The first detection resistor is connected between one input end of the buck-boost circuit and one bridge arm of the H-bridge structure, the second detection resistor is connected between one output end of the buck-boost circuit and the other bridge arm of the H-bridge structure, and the detection circuit may output a current detection signal based on resistor voltages of the first detection resistor and the second detection resistor.