Soft-Start Circuit for Detachable Tablet Power Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Detachable tablet computers experience instantaneous power shutdown when the expansion base and main system are connected or disconnected while turned on, due to uncontrolled battery discharge sequences leading to surge currents.
Innovation Solution
A hardware circuit structure with bidirectional soft-start and a comparison device to manage battery discharge between the main and auxiliary batteries, avoiding surge currents and allowing user-set reference voltages to control power distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the expansion base and main system are connected or disconnected while the tablet computer is turned on, then the device structure allows flexibility and portability, but instantaneous power shutdown occurs due to uncontrolled battery discharge sequences
Solution Approach 1:
The patent applies preliminary action by implementing a soft-start circuit that pre-charges the auxiliary battery before it begins discharging to the main system. This preliminary charging action prevents sudden current surges when the expansion base is connected, thereby avoiding instantaneous power shutdowns while maintaining detachable connection flexibility.
Solution Approach 2:
The patent uses a current limiting circuit as an intermediary component between the auxiliary battery and the main system. This intermediary controls the discharge current flow, preventing harmful current surges during connection while allowing normal power transfer, thus resolving the contradiction between connection flexibility and power stability.
2Use of energy by moving object
If the main battery device or auxiliary battery device generates surge current when supplying power to the main system, then battery power can be transferred between devices, but instantaneous power shutdown and system instability occurs
Solution Approach 1:
The patent implements beforehand cushioning by adding a soft-start circuit that gradually charges the auxiliary battery before power transfer begins. This cushioning action absorbs potential surge currents and prevents instantaneous power shutdowns, allowing safe battery power transfer between the expansion base and main system.
Solution Approach 2:
The patent converts the potentially harmful surge current into a beneficial controlled discharge process. By using a current limiting circuit, the harmful instantaneous current surge is transformed into a controlled, gradual power transfer that protects the system while maintaining the ability to transfer power between batteries.
3Extent of automation
If software monitoring is used to control battery discharge sequence, then power management can be implemented, but device complexity and software dependency increases
Solution Approach 1:
The patent applies self-service by designing a hardware circuit that automatically controls the battery discharge sequence without requiring software intervention. The current limiting circuit and soft-start circuit self-regulate the power flow based on electrical conditions, reducing device complexity and eliminating software dependency for basic power management functions.
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
Prevents instantaneous power shutdowns and allows controlled battery discharge, ensuring seamless power transitions during connection and disconnection, thereby extending battery life and user convenience.
Implementation Method 1
a voltage-directing device (108), and a switch device (104). The voltage-directing device (108) comprises a first input terminal (T1), a second input terminal (T2) and an output terminal (OUT1), and is configured to output through the output terminal the higher of the voltages at the first input terminal and the second input terminal
Implementation Method 2
a first soft-start device (110). The first soft-start device (110) is configured to connect to the auxiliary battery device (202) and output a voltage to the second input terminal (T2) when the main device (100) is connected to the expansion device (200)
Implementation Method 3
a comparison device (106). The comparison device (106) is configured to receive the voltage at the second input terminal (T2) and a reference voltage, control the switch device (104) to enter an off-state when the voltage at the second input terminal (T2) is higher than the reference voltage, and control the switch device (104) to enter an on-state when the voltage at the second input terminal (T2) is not higher than the reference voltage
Data Source
AI summary
An electronic device includes a main device and an expansion device with an auxiliary battery device. The main device includes a main battery device, a voltage-directing device, a switch device, a first soft-start device, and a comparison device. The voltage-directing device outputs, through an output terminal, the higher of the voltages at a first input terminal and a second input terminal. The first soft-start device is connected to the auxiliary battery device and outputs a voltage to the second input terminal when the main device is connected to the expansion device. The comparison device controls the switch device to enter an off-state when the voltage at the second input terminal is higher than a reference voltage, and controls the switch device to enter an on-state when the voltage at the second input terminal is not higher than the reference voltage.