Microcomputer Power Supply Switching Stability Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing microcomputers experience unstable operation of internal circuits when switching from main power supply voltage to auxiliary power supply voltage due to a large voltage difference, leading to variability in the voltage supplied.
Innovation Solution
A semiconductor device with a control circuit that manages the switching between main and auxiliary power supply voltages, ensuring the voltage variation is within a predetermined value by using switches and control circuits to gradually adjust the power supply node voltage, thereby stabilizing the operation of internal circuits.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the switching from main power supply voltage to auxiliary power supply voltage is performed directly, then the switching operation is simple and fast, but the voltage variation becomes large causing unstable operation of internal circuits
Solution Approach 1:
The control circuit performs preliminary action by detecting the voltage difference between main and auxiliary power supplies before switching occurs. When the voltage difference exceeds a predetermined threshold, the control circuit preemptively adjusts the switching timing to prevent large voltage variations, thereby ensuring stable internal circuit operation without requiring complex real-time intervention during the actual switching moment.
Solution Approach 2:
The control circuit implements feedback by continuously monitoring the voltage difference between the main power supply terminal and auxiliary power supply terminal. Based on this feedback information, the control circuit dynamically adjusts the switching control signals to the first and second switches, optimizing the switching moment to minimize voltage variation and maintain reliable internal circuit operation throughout the transition.
2Reliability
If the switching is controlled to reduce voltage variation, then the internal circuit operation becomes stable, but the switching operation becomes more complex
Solution Approach 1:
The control circuit performs self-service by autonomously detecting voltage differences and automatically generating appropriate switching control signals without external intervention. The control circuit monitors the voltage difference between main and auxiliary power supplies and independently determines the optimal switching moment, thereby reducing voltage variation and ensuring stable internal circuit operation while maintaining operational simplicity through automation.
Data Source
AI summary
A microcomputer includes a first switch coupled between a main power supply terminal and a power supply node, and a second switch coupled between an auxiliary power supply terminal and the power supply node. The microcomputer compares a voltage V1 of the main power supply terminal with a reference voltage VR1. When V1>VR1, the microcomputer turns on the first switch and turns off the second switch, and when V1<VR1, the microcomputer turns off the first switch, and turns on/off the second switch to gradually increase a voltage V3 of the power supply node. Thus, the operation of a clock generation circuit driven by V3 can be stable even when V3 is changed from V1 to V2.