Bidirectional Biasing Circuit for Stable Varactor Antenna Voltage

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Solution Overview

Problem

Existing electronic devices with varactor antennas face challenges in bidirectional biasing, requiring complementary metal-oxide-semiconductor (CMOS) processes to compensate for reverse and forward currents, which can be inefficient and complex.

Innovation Solution

An electronic device comprising a voltage source circuit and a current source circuit, electrically connected to an electronic component, forming a bidirectional biasing circuit that enables forward and reverse biasing through a network of transistors and capacitors, allowing for efficient threshold voltage compensation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If CMOS process is used to compensate reverse and forward current with source and sink current circuits, then bidirectional biasing can be achieved, but device complexity and manufacturing difficulty increase

Engineering Contradiction:
Improvebidirectional biasing capabilityVSAvoidcircuit complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The circuit is segmented into distinct functional blocks: voltage source circuit (with first transistor and first capacitor), current source circuit (with second transistor and second capacitor), and leakage compensation circuit (with third transistor and fourth transistor). Each segment handles specific compensation tasks independently, reducing overall circuit complexity while maintaining bidirectional biasing capability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies preliminary compensation actions by pre-charging capacitors and pre-positioning transistors in specific states before bidirectional operation begins. The voltage source circuit and current source circuit are prepared in advance to handle forward and reverse currents, eliminating the need for complex real-time CMOS process adjustments during operation.

Inventive Principle:
Principle #10Preliminary action

2Stability of the object's composition

If voltage-biased active-matrix pixel with source follow amplifier is used, then bias voltage stability can be maintained, but manufacturing process complexity increases

Engineering Contradiction:
Improvebias voltage stabilityVSAvoidmanufacturing process simplicity
Core Design Contradiction:
Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The circuit employs self-service mechanisms where the voltage source circuit automatically adjusts bias voltage based on detected leakage current, and the current source circuit independently compensates for reverse current. The transistors and capacitors work autonomously to maintain bias stability without requiring complex external CMOS process control, simplifying manufacturing.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent changes key parameters by using separate voltage and current source circuits with dedicated transistors and capacitors instead of traditional source follow amplifiers. This parameter change allows independent optimization of bias voltage stability while avoiding the manufacturing complexity of CMOS complementary circuits.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If traditional voltage source circuit is used without dedicated current compensation, then circuit simplicity is maintained, but bias voltage stability deteriorates due to leakage current

Engineering Contradiction:
Improvecircuit simplicityVSAvoidbias voltage stability
Core Design Contradiction:
Device complexityVSStability of the object's composition

Solution Approach 1:

The patent introduces intermediary elements (capacitors and dedicated compensation transistors) that mediate between the voltage source and the electronic component. These intermediaries buffer and compensate for leakage current effects, maintaining bias voltage stability without significantly increasing overall circuit complexity. The capacitors act as energy reservoirs that smooth out voltage fluctuations.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP4187782A1Electronic device
Publication Date: 2023.05.31 INNOLUX CORP
  • EP4187782A1 patent drawingFigure 1
  • EP4187782A1 patent drawingFigure 2A
  • EP4187782A1 patent drawingFigure 2B

AI summary

An electronic device (100, 300, 500) is provided. The electronic device (100, 300, 500) includes a voltage source circuit (110, 310, 510), a current source circuit (120, 320, 520) and an electronic component (130, 330, 530). The voltage source circuit (110, 310, 510), the current source circuit (120, 320, 520) and the electronic component (130, 330, 530) are electrically connected to a node (N0).