Single Boosted-Rail BTL Amplifier for High-Power Audio Output
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing amplifiers face inefficiencies in increasing output power, particularly in automobile stereo systems, where reducing speaker impedance to boost power results in significant parasitic losses and electromagnetic interference is a concern with high-frequency switching techniques.
Innovation Solution
The implementation of a boosted-rail amplifier with a single boosted rail operating at twice the audio signal frequency, which dynamically switches between non-boost and boost modes to increase output voltage, using a common-mode signal to track the output voltage and a boost capacitor for energy supply, allowing efficient power boosting without the need for dual rails.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If speaker impedance is reduced to increase amplifier output power, then power output increases, but parasitic losses increase significantly
Solution Approach 1:
The patent changes the voltage parameter by implementing a boosted-rail circuit that dynamically increases the supply voltage to the amplifier. By boosting the rail voltage (e.g., from 12V to higher levels), the amplifier can deliver more power to the load without needing to reduce speaker impedance, thereby avoiding increased parasitic losses while achieving higher power output
2Power
If high-frequency switching techniques are used to increase supply voltage, then output power increases, but electromagnetic interference increases
Solution Approach 1:
The patent employs high-frequency switching techniques in the boosted-rail circuit to dynamically increase the supply voltage to the amplifier, enabling higher power output. The switching operation allows the circuit to store and release energy at high frequency, achieving voltage boosting while managing electromagnetic interference through proper circuit design and filtering
3Power
If dual voice coil configuration is used to triple power output, then power increases, but peak current increases to 45 amperes
Solution Approach 1:
The patent changes the voltage parameter by implementing a boosted-rail circuit that dynamically increases the supply voltage to the amplifier. By boosting the rail voltage, the amplifier can deliver more power to the load without needing to reduce speaker impedance, thereby avoiding increased parasitic losses while achieving higher power output
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution quadruples the power output while maintaining efficiency and reducing electromagnetic interference, allowing for higher power amplification in automobile stereo systems and other applications with minimal parasitic losses.
Implementation Method 1
a boost capacitor for energy supply
Data Source
AI summary
An amplifier device including an amplifier having an input for receiving an audio input signal and an output for sending an output signal to a load. A boosted-rail circuit is connected to a power source and has a single boosted rail connected to the BTL amplifier. Also, a common-mode circuit is coupled to the boosted-rail circuit and the BTL amplifier. The common-mode circuit sends a common-mode signal to the BTL amplifier that will dynamically track the output voltage supplied from the boosted-rail circuit to the BTL amplifier. In operation, the boosted-rail circuit reacts to the BTL amplifier and switches from a non-boost mode to a boost mode to increase the output voltage supplied to the BTL when the BTL amplifier requires additional voltage.