Buffer Transistor Voltage Regulator Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional voltage regulators experience significant overshoot and undershoot in output voltage due to abrupt changes in input voltage, which can damage or malfunction load circuits, and existing solutions are costly, power-intensive, or unsuitable for battery-powered applications.
Innovation Solution
A semiconductor circuit with a buffer transistor, specifically an n-channel depletion-mode metal-oxide semiconductor field effect transistor, is introduced between the power supply and voltage regulator, which acts as a constant current circuit to buffer sudden changes in input voltage, preventing abrupt transitions in output voltage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional voltage regulator circuitry is used, then the output voltage can be regulated to a constant level, but the output voltage experiences sharp transient changes (overshoot and undershoot) when the input voltage suddenly changes
Solution Approach 1:
The patent introduces a buffer transistor circuit as an intermediary element between the input voltage source and the voltage regulator. This buffer transistor (M21) acts as a mediator that isolates the regulator circuitry from abrupt input voltage changes, preventing these changes from directly affecting the output voltage. The buffer transistor absorbs the shock of sudden voltage transitions, thereby eliminating overshoot and undershoot while maintaining reliable output voltage regulation.
2Reliability
If existing solutions to prevent voltage transient changes are implemented, then output voltage stability improves, but the solutions are costly, power-intensive, or unsuitable for battery-powered applications
Solution Approach 1:
The buffer transistor circuit is designed to operate autonomously without requiring additional power supply connections or external control signals. The transistor automatically activates when input voltage changes occur, using the existing power supply voltage itself to control its operation. This self-service mechanism prevents voltage transient issues without adding extra power consumption, making the solution ideal for battery-powered applications.
3Reliability
If existing solutions to prevent voltage transient changes are implemented, then output voltage stability improves, but the device complexity and cost increase
Solution Approach 1:
The patent segments the voltage regulation system into two distinct functional blocks: a buffer stage (transistor M21) and a regulation stage (existing voltage regulator circuitry). This segmentation allows the simple buffer transistor to handle the complex task of preventing voltage transient changes, while the main regulator circuitry can focus on its primary function of maintaining constant output voltage. The segmentation reduces overall system complexity compared to redesigning the entire regulator circuit.
Solution Approach 2:
The buffer transistor serves multiple functions simultaneously: it acts as a voltage buffer, a transient change absorber, and a protection element for the downstream regulator circuitry. By making this single component multi-functional, the patent avoids the need for additional specialized components that would increase device complexity and cost, while still achieving reliable output voltage stability.
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 solution effectively reduces overshoot and undershoot in output voltage, protecting load circuits while minimizing power consumption and being suitable for battery-powered applications, with the buffer transistor providing fast response times and cost-effective operation.
Implementation Method 1
a buffer transistor M21, being a depletion-mode n-channel metal-oxide semiconductor field effect transistor
Data Source
AI summary
A semiconductor circuit includes a voltage regulator and a buffer transistor. The voltage regulator converts an input voltage input to an input terminal thereof into an output voltage output to an output terminal thereof. The buffer transistor is an n-channel depletion-mode metal-oxide semiconductor field effect transistor, disposed between the power supply terminal and the voltage regulator with a gate terminal thereof connected to the power supply terminal, a drain terminal thereof connected to the power supply terminal, and a source terminal thereof connected to the input terminal of the voltage regulator.