Voltage Regulator Feedback Circuit for Fast, Accurate Output
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Voltage regulators in battery management systems face challenges in providing a regulated output voltage with high accuracy and low impedance, especially over a wide range of load currents and supply voltages, while maintaining low quiescent current consumption and being insensitive to temperature, process, and environmental variations.
Innovation Solution
A voltage regulator design featuring a reference current generator and a regulator stage with a NMOS transistor, bipolar current mirror, and output resistors arranged in a negative feedback loop, where the bipolar transistors and resistors are matched to ensure temperature independence and high accuracy, and additional voltage reference blocks can be used to compensate for temperature variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If conventional voltage regulator circuits are used, then the circuit can provide voltage regulation, but the output impedance is high resulting in slow transient response to load variations
Solution Approach 1:
The patent implements a negative feedback loop where the output voltage is fed back through a resistive divider network to the error amplifier. This feedback mechanism continuously monitors output voltage variations and adjusts the pass transistor gate voltage to maintain constant output voltage, thereby achieving low output impedance and fast transient response to load variations.
Solution Approach 2:
The patent uses a dynamic compensation network with resistors and capacitors that automatically adjust the frequency response characteristics based on operating conditions. The compensation circuit dynamically modifies the error amplifier's behavior to maintain stability while achieving fast transient response across varying load currents and temperatures.
2Measurement precision
If the regulator is designed for high accuracy over wide supply voltage range, then voltage regulation accuracy improves, but quiescent current consumption increases
Solution Approach 1:
The patent employs a reference voltage circuit that generates a temperature-compensated reference voltage using a bandgap reference technique. This reference voltage remains stable across wide supply voltage ranges and temperature variations, enabling high regulation accuracy without requiring excessive bias current. The circuit dynamically adjusts operating parameters to maintain precision while minimizing quiescent current consumption.
Solution Approach 2:
The patent implements power management circuitry that adjusts the regulator's operating mode based on load requirements. During light load or quiescent conditions, the circuit reduces bias currents and switches to a low-power mode, while maintaining full regulation capability when load demands increase, thus achieving high accuracy without continuously consuming excessive quiescent current.
3Stability of the object's composition
If temperature compensation circuits are added to reduce sensitivity to temperature variations, then temperature stability improves, but device complexity increases
Solution Approach 1:
The patent integrates temperature compensation functionality directly into the reference voltage generation circuit using a bandgap reference architecture. The compensation network combines PTAT (proportional to absolute temperature) and CTAT (complementary to absolute temperature) voltage components within the same circuit block, achieving temperature stability without adding separate compensation stages or increasing overall device complexity.
4Measurement precision
If the regulator stage uses high current to maintain fixed output voltage over wide load range, then voltage accuracy improves, but power loss increases
Solution Approach 1:
The patent implements a dynamic load regulation mechanism where the error amplifier continuously adjusts the pass transistor's conduction state based on actual load current demands. The compensation network dynamically optimizes the feedback loop response, allowing the regulator to maintain high output voltage accuracy across wide load ranges while minimizing excess current flow and associated power losses by adapting to real-time operating conditions.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A voltage regulator comprising a reference current generator coupled between a supply terminal and a reference terminal and configured to provide a reference current that is independent of an operating range of a supply voltage; and a regulator stage comprising: a current terminal configured to receive the reference current; a NMOS transistor having: a gate coupled to the current terminal; a drain coupled to the supply terminal; and a source coupled to an output terminal; a voltage reference circuit for providing a regulated output voltage coupled between the output terminal and the reference terminal, the voltage reference circuit comprising an output resistor coupled in series with a conduction channel of an output bipolar transistor arranged in a diode-connected configuration; an input bipolar transistor having: a conduction channel coupled between the current terminal and the reference terminal; and a base terminal coupled to a base terminal of the output bipolar transistor.