High-Side Level Shifter With Dynamic Resistance for Heat-Delay Tradeoff
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High voltage integrated circuits face a trade-off between heat generation and propagation delay characteristics, particularly at high frequencies, where reducing drain currents or gate-ON times either increases propagation delay or introduces noise, limiting the ability to discharge output capacitance and stabilize signals.
Innovation Solution
Incorporating a high-side voltage detection circuit with a switching device that adjusts resistance based on detected voltage levels, allowing for reduced drain currents and minimized heat generation while maintaining signal propagation efficiency by using N-channel MOSFETs and diodes in the level shifter circuit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If drain currents are reduced to minimize heat generation, then heat loss decreases, but propagation delay increases and signal stability deteriorates
Solution Approach 1:
The patent applies dynamics by making the resistance value changeable based on operating conditions. The level shifter circuit includes a switching device that dynamically adjusts the resistance between the common voltage terminal and the source terminal of the high voltage transistor. During switching operations, the resistance is reduced to enable faster discharge of output capacitance and shorter propagation delay. During steady-state operation, the resistance is increased to reduce drain current and minimize heat generation. This dynamic adaptation resolves the contradiction between heat loss and propagation delay.
2Productivity
If gate-ON times are reduced to increase switching frequency, then productivity increases, but noise increases and signal stability deteriorates
Solution Approach 1:
The patent uses dynamics by dynamically adjusting the resistance in the level shifter circuit based on the switching phase. During the gate-ON period, the resistance is reduced to provide sufficient current drive for fast switching and to maintain signal stability against noise. During the gate-OFF period or steady-state, the resistance is increased to reduce power consumption and heat generation. This allows the circuit to achieve high switching frequencies while maintaining signal integrity and reducing noise susceptibility.
3Loss of energy
If resistance in level shifter is increased to reduce drain current, then heat generation decreases, but ability to discharge output capacitance deteriorates
Solution Approach 1:
The patent resolves this contradiction by making the resistance dynamic rather than fixed. The level shifter circuit incorporates a switching device that changes the resistance value based on the operational phase. When capacitance discharge is required (during switching transitions), the resistance is reduced to enable fast discharge of the output capacitance of the high voltage transistor. During normal operation when high current is not needed, the resistance is increased to reduce heat generation. This time-varying resistance optimization allows the circuit to achieve both low heat generation and fast switching capability.
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 improves the trade-off between heat generation and propagation delay, enabling higher switching frequencies with reduced heat loss and stable signal propagation by dynamically controlling drain currents and output capacitance.
Implementation Method 1
N-channel MOSFETs and diodes in the level shifter circuit
Data Source
AI summary
In a level shifter circuit that transmits a set signal and a reset signal input to input terminals of a high-side latch circuit, the source sides of high voltage transistors are connected to current negative feedback resistors, and transistors are connected in parallel to the current negative feedback resistors. Further included is a high-side voltage detection circuit that detects whether the voltage of a high-side power supply terminal is a high voltage. When a high voltage is detected, the transistors are turned OFF to make the drain currents that flow smaller, thereby making it possible to improve the trade-off between heat generation and propagation delay characteristics in the high voltage transistors.