Audio Gain Compression Circuit for Noise-Aware Analog Output

Solution Overview

Problem

Electronic devices face issues with information loss and noise inclusion when converting digital audio signals to analog outputs, leading to degraded audio quality due to the discrete nature of digital domains and noise introduction in analog domains.

Innovation Solution

Implementing an electronic circuit with a peak detector, gain controller, and compressor to dynamically adjust digital gains, ensuring that the peak level of digital inputs is increased to a target level while maintaining a controlled ratio of gain increment to peak level decrement, thereby reducing noise and improving signal-to-noise ratio (SNR) and dynamic range.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If digital gain is increased to raise peak level to target level, then audio signal quality is improved, but noise is also amplified leading to degraded signal-to-noise ratio

Engineering Contradiction:

Improvepeak level accuracyVSAvoidnoise

Core Design Contradiction:

Measurement precisionVSObject-generated harmful factors

Solution Approach 1:

The patent implements dynamic gain control where the digital gain value changes based on the detected peak level. The gain controller adjusts the gain in real-time according to the input signal characteristics, transitioning from fixed gain to adaptive gain modulation. This resolves the contradiction by optimizing the signal-to-noise ratio dynamically rather than using a static gain value that would either amplify noise excessively or fail to raise the peak level sufficiently.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent employs a feedback mechanism where the peak detector continuously monitors the peak level of the digital input signal and feeds this information back to the gain controller. The gain controller then adjusts the digital gain based on this feedback to maintain the peak level at the target level. This closed-loop control system resolves the contradiction by automatically optimizing the gain setting to improve signal quality while minimizing noise amplification through intelligent gain adjustment.

Inventive Principle:

Principle #23Feedback

2Measurement precision

If digital gain is increased to improve signal level, then audio quality is enhanced, but power consumption increases

Engineering Contradiction:

Improvesignal levelVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent implements dynamic gain control where the digital gain value changes based on the detected peak level. The gain controller adjusts the gain in real-time according to the input signal characteristics, transitioning from fixed gain to adaptive gain modulation. This resolves the contradiction by optimizing the signal-to-noise ratio dynamically rather than using a static gain value that would either amplify noise excessively or fail to raise the peak level sufficiently.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent changes the gain parameter dynamically based on the peak level detection. Instead of using a constant high gain value that would always consume maximum power, the system adjusts the gain parameter according to the actual signal requirements. When the peak level is already close to the target level, the gain is reduced, thereby lowering power consumption while maintaining audio quality.

Inventive Principle:

Principle #35Parameter changes

3Measurement precision

If gain control is applied to raise peak level, then dynamic range is improved, but distortion may occur when peak level exceeds maximum allowable level

Engineering Contradiction:

Improvedynamic rangeVSAvoidsignal integrity

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent applies preliminary gain control before the signal reaches the maximum allowable level. The peak detector identifies upcoming peaks and the gain controller pre-adjusts the gain to ensure the peak level reaches but does not exceed the target level. This preventive approach resolves the contradiction by maintaining dynamic range improvement while avoiding signal distortion through anticipatory gain management.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent employs a feedback mechanism where the peak detector continuously monitors the peak level of the digital input signal and feeds this information back to the gain controller. The gain controller then adjusts the digital gain based on this feedback to maintain the peak level at the target level. This closed-loop control system resolves the contradiction by automatically optimizing the gain setting to improve signal quality while minimizing noise amplification through intelligent gain adjustment.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS10320408B2Electronic circuit performing gain control and gain compression to improve characteristic of analog output and electronic device including the same

Publication Date: 2019.06.11 SAMSUNG ELECTRONICS CO LTD

AI summary

An electronic circuit includes a peak detector, a gain controller, and a compressor. The peak detector detects a peak level from a digital input. The gain controller outputs a digital gain with regard to increasing the peak level to a target level, The compressor provides the gain controller with a compressed gain which is to be output as the digital gain, based on the detected peak level. In a compression interval where the peak level is greater than a threshold level, the output digital gain increases as the peak level decreases. The compressor generates the compressed gain such that a ratio of an increment of the output digital gain to a decrement of the peak level in the compression interval is less than a reference ratio.