Voltage Switch Circuit Using Low Voltage Transistors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High voltage Integrated Circuits (ICs) face challenges in reducing silicon area and simplifying manufacturing due to the need for High Voltage (HV) transistors, which require additional processing steps and masks, and often necessitate the use of HV transistors for voltage switches, complicating the technology and increasing silicon area usage.
Innovation Solution
A circuit topology using only Low Voltage (LV) transistors is implemented for voltage switches, with a biasing mechanism that alternately couples output terminals with input terminals while isolating the other, ensuring voltage differences across LV transistors do not exceed their maximum rating, allowing for the handling of high voltage differences without HV transistors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If High Voltage transistors are used in voltage switches, then the circuit can handle high voltage differences, but the silicon area increases and manufacturing complexity increases
Solution Approach 1:
The patent divides the high voltage path into multiple segments by using several LV transistors connected in series. Each transistor handles a portion of the total voltage difference, ensuring that no single transistor exceeds its maximum voltage rating while collectively managing the full high voltage range.
Solution Approach 2:
The patent introduces intermediate voltage nodes between the input terminals and output terminal. These intermediate nodes serve as mediators that distribute the voltage stress across multiple LV transistors, allowing the circuit to handle high voltage differences without requiring HV transistors.
2Reliability
If High Voltage transistors are used in voltage switches, then the circuit can handle high voltage differences, but the manufacturing process becomes more complex
Solution Approach 1:
The patent makes the same LV transistor design serve multiple functions by using it in series configurations for different voltage ranges. The biasing mechanism enables these transistors to adaptively handle various voltage conditions, eliminating the need for separate HV transistor designs and their associated manufacturing complexity.
Solution Approach 2:
The patent changes the operational parameters (gate voltages) of LV transistors through a biasing mechanism to enable them to handle high voltage differences. By dynamically adjusting the gate voltages, the transistors can safely operate under high voltage conditions without requiring physical modifications to their structure or manufacturing process.
3Adaptability or versatility
If High Voltage transistors are used, then voltage switches can manage high voltage differences, but the technology complexity increases
Solution Approach 1:
The patent introduces a dynamic biasing mechanism that actively adjusts the gate voltages of LV transistors based on the input voltage conditions. This dynamic control enables the same static LV transistor structure to adaptively handle varying voltage ranges, providing versatility without increasing transistor type diversity.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A circuit is disclosed. The circuit comprises a first input terminal (INA1), a second input terminal (INA2) and an output terminal (OUT). The circuit further includes a first circuital branch (610) connected between the first input terminal and the output terminal, and a second circuital branch (620) connected between the second input terminal and the output terminal. The first circuital branch is selectively activatable for coupling the first input terminal with the output terminal, and the second circuital branch is selectively activatable for coupling the second input terminal with the output terminal. The first and second circuital branches comprise each at least one electronic device having at least a first and a second device terminals. Said at least one electronic device is designed to guarantee the capability of sustaining voltage differences across at least the first and second device terminals thereof that are up-limited in absolute value by a first predetermined maximum value lower than the maximum of absolute values of voltage differences between the output terminal and the first input terminal, and between the output terminal and the second input terminal, respectively.