Power Amplifier Bias Circuit for Low-Voltage Current Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power amplifier modules consume excessive current in low power modes, particularly when the power supply voltage is relatively low, and simply adjusting the number of operating unit transistors is insufficient to reduce current consumption effectively.
Innovation Solution
A power amplifier module comprising first and second amplifiers, a first bias circuit, and an adjusting circuit, where the adjusting circuit includes a transistor with three terminals, with a power supply voltage applied to one terminal and a bias drive signal-based voltage to another, allowing the bias current to be adjusted based on the power supply voltage, enabling the transistor to operate as two p-n junction diodes at low voltages and reducing current consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the number of operating unit transistors is adjusted according to power mode, then power amplification is suitable for selected power mode, but current consumption is not sufficiently reduced in low power mode
Solution Approach 1:
The patent changes the operating parameters of the transistor by adjusting the bias current based on power supply voltage. When power supply voltage is low, the bias current is reduced, which allows the transistor to operate more efficiently at low voltages and reduces current consumption while maintaining suitable power amplification
Solution Approach 2:
The patent dynamically adjusts the bias current according to the power supply voltage level. The adjusting circuit monitors the power supply voltage and modifies the bias current accordingly, enabling the power amplifier to adapt its operating characteristics in real-time to minimize current consumption in low power modes
2Power
If bias current is increased for adequate power amplification, then power amplification performance is improved, but current consumption increases in low power mode
Solution Approach 1:
The patent optimizes the bias current parameter based on the power supply voltage. By reducing the bias current when the power supply voltage is low, the system achieves adequate power amplification performance with reduced current consumption, resolving the contradiction between maintaining performance and reducing energy use
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 configuration reduces the current flowing through the transistors when the power supply voltage is low, decreasing the overall current consumption and maintaining suitable power amplification, while minimizing the impact of noise in the amplified signal.
Implementation Method 1
enabling the transistor to operate as two p-n junction diodes at low voltages
Data Source
AI summary
A power amplifier module includes first and second amplifiers, a first bias circuit, and an adjusting circuit. The first amplifier amplifies a first signal. The second amplifier amplifies a second signal based on an output signal from the first amplifier. The first bias circuit supplies a bias current to the first amplifier via a current path on the basis of a bias drive signal. The adjusting circuit includes an adjusting transistor having first, second, and third terminals. A first voltage based on a power supply voltage is supplied to the first terminal. A second voltage based on the bias drive signal is supplied to the second terminal. The third terminal is connected to the current path. The adjusting circuit adjusts the bias current on the basis of the power supply voltage supplied to the first amplifier.