Self-Starting Bandgap Cell Without Auxiliary Start-Up Circuitry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bandgap cells require auxiliary start-up circuitry, which can malfunction at nanoampere current levels, leading to interference or failure in generating a reference voltage, and occupy valuable chip area.
Innovation Solution
A self-starting bandgap cell design that utilizes a negative threshold transistor, an amplifier with a resistor string, and externally supplied bias current to generate a reference voltage without the need for auxiliary start-up circuitry.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If auxiliary start-up circuitry is used to generate reference voltage, then the bandgap cell can be started up, but the start-up circuitry may malfunction at nanoampere current levels, leading to interference or failure in generating reference voltage
Solution Approach 1:
The patent removes the auxiliary start-up circuitry from the bandgap cell design. The negative threshold transistor inherently provides self-starting capability through its negative threshold voltage characteristic, which automatically generates the necessary bias current without requiring external start-up circuitry. This extraction of unnecessary components eliminates the reliability issues associated with start-up circuit malfunction while reducing overall device complexity.
Solution Approach 2:
The bandgap cell is designed to be self-starting through the use of a negative threshold transistor that automatically generates the required bias current. The transistor's inherent negative threshold voltage characteristic enables it to turn on and establish current flow without external assistance, making the system self-sufficient and eliminating the need for separate start-up circuitry that could malfunction.
2Reliability
If auxiliary start-up circuitry is used in bandgap cell, then startup can be achieved, but valuable chip area is occupied by additional circuitry
Solution Approach 1:
The patent eliminates auxiliary start-up circuitry from the design, using only the negative threshold transistor to provide self-starting capability. This removal of redundant components significantly reduces the chip area occupied by start-up circuitry while maintaining reliable startup operation through the transistor's inherent negative threshold voltage characteristic.
3Reliability
If auxiliary start-up circuitry is used, then bandgap cell can start up, but additional power is consumed and power waste occurs
Solution Approach 1:
The patent removes auxiliary start-up circuitry that would consume additional power. The negative threshold transistor provides self-starting capability without requiring external power-consuming circuits, thereby reducing overall power consumption and eliminating energy waste associated with maintaining separate start-up circuitry.
Solution Approach 2:
The bandgap cell uses the negative threshold transistor's inherent characteristics to generate its own bias current and achieve startup without external assistance. This self-service mechanism eliminates the need for power-consuming auxiliary start-up circuitry, reducing overall power consumption while ensuring reliable startup capability.
Data Source
AI summary
A self-starting bandgap cell for generating a reference voltage.