Integrated Feedback Level Shifter for Pulse-Free DC-DC Switching

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional pulse-triggered level shifter circuits require additional pulse generator circuits, leading to potential maloperation and increased power consumption due to the need for precise pulse duration selection, which is critical for safe and efficient operation in high-voltage DC-DC converters.

Innovation Solution

Integration of command and feedback circuits into a single level shifter circuit, eliminating the need for separate pulse generators, with temporally limited current pulses ensuring state changes without additional circuitry, enhancing reliability and reducing energy consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If separate pulse generator circuits are used in conventional level shifters, then state changes can be triggered, but power consumption increases and reliability decreases due to precise pulse duration requirements

Engineering Contradiction:

ImprovereliabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent combines the command level shifter and feedback level shifter into a single integrated circuit block, eliminating the need for separate pulse generator circuits. The feedback signal from the second level shifter directly triggers the first level shifter, creating a self-sustaining operation that reduces power consumption and eliminates timing-critical pulse generation requirements.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The integrated level shifter circuit uses its own feedback output signal to trigger its command input signal through the feedback path. This self-service mechanism eliminates external pulse generators and reduces power consumption by only activating circuits when state changes are actually needed, rather than requiring continuous or precisely-timed external pulses.

Inventive Principle:

Principle #25Self-service

2Reliability

If separate pulse generator circuits are used, then state changes can be controlled, but device complexity increases

Engineering Contradiction:

ImprovereliabilityVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges two separate level shifter circuits and their associated pulse generators into one integrated circuit. This consolidation reduces device complexity by eliminating redundant components while maintaining the dual functionality of command signal transmission and feedback signal transmission between voltage domains.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The integrated level shifter circuit performs multiple functions: it acts as both a command level shifter and a feedback level shifter, and simultaneously generates the triggering pulses for state changes. This multi-functionality reduces overall device complexity by having one circuit block perform what previously required multiple separate circuits.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Use of energy by moving object

If pulse duration is set too short, then power consumption is reduced, but state changes may not be guaranteed

Engineering Contradiction:

Improvepower consumptionVSAvoidstate change guarantee

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The patent implements a feedback path where the output of the second level shifter is fed back to trigger the first level shifter. This feedback mechanism ensures that state changes are reliably detected and responded to, eliminating the need for long pulse durations to guarantee state changes. The feedback provides inherent timing control based on actual signal transitions rather than fixed pulse widths.

Inventive Principle:

Principle #23Feedback

4Reliability

If pulse duration is set too long, then state changes are guaranteed, but power consumption increases

Engineering Contradiction:

Improvestate change guaranteeVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The integrated level shifter operates in a periodic, event-driven manner where circuits are activated only when signal transitions occur. The feedback mechanism creates a natural periodic operation cycle: command signal changes trigger state changes, which generate feedback signals that trigger the next state change. This periodic action eliminates the need for continuously long pulses, reducing power consumption while ensuring state changes occur when needed.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS11777476B2Level shifter circuit with integrated feedback circuit, dc-dc converter, and method

Publication Date: 2023.10.03 NXP USA INC

AI summary

There is described a pulse-triggered level shifter circuit comprising: i) a command circuit configured to shift a command input signal of a first voltage domain to a command output signal of a second voltage domain, the command circuit comprising: a) a command input stage for receiving the command input signal, and b) a command output stage for providing the command output signal; and ii) a feedback circuit coupled to the command circuit and configured to shift a feedback input signal of a third voltage domain to a feedback output signal of a forth voltage domain, the feedback circuit comprising: c) a feedback input stage for receiving the command output signal as the feedback input signal, and d) a feedback output stage for providing the feedback output signal. The command circuit and the feedback circuit are hereby integrated into one single level shifter circuit.