Voltage Regulator Boost Circuit for Low-Current Transient Response
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing voltage regulators face challenges in reducing current consumption due to constant current flow through multiple paths, making it difficult to manage sudden fluctuations in output voltage effectively.
Innovation Solution
A voltage regulator design that includes a boost transistor with a diode to limit the gate voltage, a capacitor to boost the gate voltage, and a constant current driving transistor forming a current mirror with the boost transistor, which reduces the peak value of the boost current and minimizes constant current flow paths.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a constant current is used to limit the upper limit of the boost current through a current mirror circuit, then the peak value of output voltage fluctuation is reduced, but current consumption increases due to constant current flowing through multiple paths
Solution Approach 1:
The patent replaces the static constant current mirror circuit with a dynamic control mechanism using a capacitor and diode. The capacitor stores charge to dynamically boost the gate voltage of the boost transistor only when needed (during output voltage fluctuations), while the diode ensures unidirectional current flow. This dynamic approach allows the boost current to be activated temporarily for stability control and then deactivated, eliminating continuous current consumption through the current limit path while maintaining output voltage stability.
2Speed
If a boost transistor is added in parallel with the constant current source to improve responsiveness, then the response to sudden output voltage changes is enhanced, but the complexity of the circuit increases
Solution Approach 1:
The patent merges the functions of the constant current source and the boost transistor by connecting the boost transistor in parallel with the constant current source. Both components share the same connection points: the constant current source provides a baseline current, while the boost transistor activates in parallel to provide additional current during fluctuations. This merging allows the circuit to achieve enhanced responsiveness without requiring separate independent control circuits, thereby limiting the increase in overall circuit complexity.
3Adaptability or versatility
If three current paths are maintained for constant current flow (error amplifier, filter, and boost current limit), then the voltage regulator can handle various operating conditions, but it becomes difficult to reduce current consumption in use states
Solution Approach 1:
The patent extracts the boost current limiting function from the constant current mirror circuit and implements it separately using a diode connected to the gate of the boost transistor. This extraction allows the main constant current paths (error amplifier and filter) to continue operating for adaptability, while the boost transistor path is controlled independently through the diode and capacitor mechanism. The boost path is activated only during transient fluctuations rather than continuously, reducing current consumption while preserving the ability to handle various operating conditions through the remaining constant current paths.
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
This configuration suppresses the peak value of the boost current, reduces current consumption, and enhances the responsiveness of the voltage regulator to sudden output voltage increases, while eliminating constant current flow paths.
Implementation Method 1
a capacitor that has one end connected to the output terminal
Implementation Method 2
a diode that has an anode connected to the other end of the capacitor and a cathode connected to a ground terminal
Implementation Method 3
a constant current driving transistor that forms a current mirror with the boost transistor and drives the boost transistor by a constant current
Data Source
AI summary
A voltage regulator that outputs, from an output terminal, as an output voltage, a power supply voltage that is input from an input terminal, the voltage regulator including an error amplifier that includes a constant current source that causes a current that is based on a constant current supplied from an outside to flow, and outputs a signal that is based on a difference between a feedback voltage obtained by dividing the output voltage and a reference voltage, an output transistor that has a source connected to the input terminal, a drain connected to the output terminal, and a gate connected to an output of the error amplifier, a capacitor that has one end connected to the output terminal, a boost transistor that is connected in parallel with the constant current source and that has a gate connected to another end of the capacitor, and a diode that has an anode connected to the other end of the capacitor and a cathode connected to a ground terminal.