Two-Stage Operational Amplifier With Split Supplies to Prevent Locking
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Solution Overview
Problem
Existing operational amplifiers face challenges in achieving low noise, low power consumption, and small area due to limitations in integrating class AB input stage circuits, which often result in locking issues and inefficient performance.
Innovation Solution
The operational amplifier is designed with a two-stage architecture, utilizing a class AB input stage circuit for the first-stage operational amplification and a separate power voltage for each stage, ensuring the first-stage operates with a higher voltage than the second-stage, preventing locking and optimizing power consumption and area.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a class AB input stage circuit is used to reduce noise and power consumption, then noise performance and power efficiency improve, but locking issues occur and operational stability deteriorates
Solution Approach 1:
The operational amplifier is divided into two independent stages, each with separate power voltage supplies. The first stage uses a first power voltage signal while the second stage uses a second power voltage signal, allowing independent optimization of each stage's operating conditions and preventing locking issues that would occur in a unified class AB configuration
Solution Approach 2:
Different power voltage signals are applied to different stages of the operational amplifier. The first stage receives a first power voltage signal optimized for its specific requirements, while the second stage receives a second power voltage signal tailored to its needs, enabling each stage to operate in its optimal region without causing locking
2Area of stationary object
If a class AB input stage circuit is used to reduce occupied area, then area efficiency improves, but integration complexity increases
Solution Approach 1:
The two-stage architecture with separate power supplies simplifies the integration of class AB input stage circuitry by isolating the complex first stage from the second stage, allowing independent design and optimization of each stage's area requirements without increasing overall integration complexity
3Reliability
If the first stage operates at higher voltage to prevent locking, then operational stability improves, but power consumption increases
Solution Approach 1:
The first stage is supplied with a first power voltage signal at a higher voltage level to maintain operational stability and prevent locking, while the second stage is supplied with a second power voltage signal at a lower voltage level to reduce overall power consumption, achieving both stability and efficiency through localized voltage optimization
Data Source
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AI summary
This application provides an operational amplifier, a chip, and an electronic device, and relates to the field of integrated circuit technologies. The operational amplifier includes a first power voltage end, a second power voltage end, a first-stage operational amplification circuit, and a second-stage operational amplification circuit. The first power voltage end is configured to receive a first power voltage signal, the second power voltage end is configured to receive a second power voltage signal, and a voltage value of the first power voltage signal is greater than a voltage value of the second power voltage signal. The first-stage operational amplification circuit is configured to: receive an input signal via a signal input end, and amplify the input signal under enabling control of the first power voltage signal, to generate a first drive signal. The second-stage operational amplification circuit is configured to: generate an output signal based on the first drive signal under enabling control of the second power voltage signal, and output the output signal via a signal output end. The operational amplifier has performance like low noise, low power consumption, high rate, and small area, and can be used in a chip.