Integrated Feedback Resistor Power IC for Stable Switching Supply Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power ICs require an externally connected feedback resistor for generating feedback voltage, leading to increased components, reduced noise tolerance, difficulty in controlling output voltage, and the need for dual overvoltage protection and open/short protection for the feedback resistor terminal.
Innovation Solution
A power IC with an integrated feedback resistor and output feedback controller on a single semiconductor substrate, where the feedback resistor is a polysilicon resistor with a withstand voltage of 100 V or higher, eliminating the need for external resistors and enhancing noise tolerance and control capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a feedback resistor is externally connected to generate feedback voltage, then the power IC can perform output feedback control, but the number of components increases and noise tolerance decreases
Solution Approach 1:
The feedback resistor is integrated into the power IC chip together with the output feedback controller, merging two previously separate components (external resistor and controller) into a single integrated device. This reduces the total number of components and improves noise tolerance by eliminating external connections and reducing parasitic elements.
2Ease of operation
If a feedback resistor is externally connected, then feedback voltage can be generated, but control of output voltage becomes difficult and dual overvoltage protection is required
Solution Approach 1:
The feedback resistor and output feedback controller are merged into a single integrated circuit, enabling centralized control of output voltage and unified protection mechanisms. This integration simplifies the control architecture and eliminates the need for separate protection circuits for the feedback resistor terminal.
3Reliability
If a feedback resistor is externally connected, then feedback function is achieved, but open/short protection for feedback resistor terminal is necessary
Solution Approach 1:
By integrating the feedback resistor directly into the power IC chip, the feedback path becomes internal and protected. The integrated structure eliminates external terminals for the feedback resistor, removing the need for open/short protection circuits while maintaining feedback stability through controlled internal connections.
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 integration of the feedback resistor and controller within the power IC reduces component count, improves noise tolerance, and simplifies voltage control, eliminating the need for external protection mechanisms and allowing for reliable overvoltage protection.
Implementation Method 1
a feedback resistor configured to generate a feedback voltage by dividing the output voltage of the switching power supply or a voltage commensurate with the output voltage of the switching power supply; The feedback resistor is a polysilicon resistor with a withstand voltage of 100 V or higher
Data Source
AI summary
This power supply IC is a semiconductor integrated circuit device serving as a main part for controlling a switching power supply and is formed by integrating a feedback resistor and an output feedback control unit on a single semiconductor substrate, said feedback resistor generating a feedback voltage by dividing the output voltage of the switching power supply (or the induced voltage appearing across an auxiliary winding provided on the primary side of a transformer included in an insulation-type switching power supply), said output feedback control unit performing output feedback control of the switching power supply in accordance with the feedback voltage. The feedback resistor is a polysilicon resistor having a withstand voltage of 100 V or more. A high-voltage region having higher withstand voltage in the substrate thickness direction than the other region is formed in the semiconductor substrate, and the feedback resistor is formed on the high-voltage region.