N-Type LDO Regulator With Switched-Capacitor Gate Boosting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional linear voltage regulators (LDOs) for high voltage and high current applications require a large implementation area and are limited by significant output voltage ripples, making them inefficient for battery charging in portable devices.
Innovation Solution
A voltage regulator design incorporating a N-type power switch, an error amplifier, and a switch capacitor circuit that operates in iterative phases to control the power switch, reducing output ripple voltage and allowing for smaller implementation area without the need for high input rail voltage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If conventional LDO circuits are designed for high voltage and high current capability, then the charging speed and power delivery are improved, but the implementation area increases and output voltage ripples become significant
Solution Approach 1:
The patent segments the power delivery function by using a bootstrap circuit to generate a boosted voltage that drives the N-type power switch, separating the voltage boosting function from the power delivery function. This allows high current capability with smaller device area compared to conventional approaches.
Solution Approach 2:
The patent employs dynamic voltage boosting through the bootstrap circuit, where the voltage at the gate of the N-type power switch is dynamically increased above the input voltage rail. This dynamic voltage enhancement enables the power switch to handle high voltage and current with reduced area compared to static design approaches.
2Productivity
If conventional LDO circuits are designed for high voltage and high current capability, then the charging speed is improved, but output voltage ripples become significant
Solution Approach 1:
The patent incorporates an error amplifier that provides feedback control to regulate the output voltage. The error amplifier compares the output voltage with a reference voltage and adjusts the bootstrap circuit operation accordingly, reducing output voltage ripples while maintaining high charging speed.
Solution Approach 2:
The bootstrap circuit operates in periodic phases, charging the bootstrap capacitor during one phase and discharging it to boost the gate voltage during another phase. This periodic operation enables controlled high current delivery with reduced voltage ripples through rhythmic power transfer.
3Area of stationary object
If N-type power switch is used with bootstrap circuit, then the implementation area is reduced and power capability is improved, but the control circuit complexity increases
Solution Approach 1:
The patent merges the voltage boosting function and power switch control into a single bootstrap circuit integrated with the error amplifier. This integration reduces the need for separate control circuits and external components, achieving area reduction without excessive complexity increase.
Solution Approach 2:
The bootstrap circuit serves multiple functions: it boosts the gate voltage for the N-type power switch, provides voltage regulation through the error amplifier, and enables high current capability. This multi-functionality reduces the need for separate dedicated circuits, balancing area reduction with acceptable complexity.
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 output ripple voltage, enabling a more compact design capable of handling high current and voltage while maintaining efficient voltage regulation across a wide input range, with reduced output capacitance requirements.
Implementation Method 1
a first capacitor coupled to a network of switches, the switch capacitor circuit having a first port coupled to an output the error amplifier
Implementation Method 2
in the second phase the second port is coupled to the third port via a path comprising the first capacitor
Data Source
AI summary
A voltage regulator and a corresponding method of regulating a voltage are presented. The voltage regulator includes an N-type power switch, an error amplifier, and a switch capacitor circuit. The switch capacitor circuit includes a first capacitor coupled to a network of switches, the switch capacitor circuit has a first port coupled to an output the error amplifier, a second port coupled to an output terminal of the power switch, and a third port coupled to a control terminal of the power switch. The switch capacitor circuit is iteratively operable between a first phase and a second phase. In the first phase the first port is coupled to ground via a path comprising the first capacitor, and in the second phase the second port is coupled to the third port via a path comprising the first capacitor. The voltage regulator may be implemented as a low dropout regulator.