Hybrid Amplifier Element for Uniform High-Voltage Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Series connections of amplifier elements face challenges in maintaining linear voltage distribution and efficient control voltage supply, especially at high frequencies, due to issues with optocouplers causing crosstalk and phase shifts, and the need for individual operating point adjustments, which leads to non-uniform voltage distribution and reduced bandwidth.
Innovation Solution
A hybrid amplifier element with a decoupling unit that includes a buffer input, output, and a voltage divider connected in parallel to the power path, providing a reference potential and influencing current based on voltage differences, to ensure uniform voltage distribution and reduce parasitic currents across the voltage divider chain.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If optocouplers are used to supply control voltages to series-connected amplifier elements, then potential isolation is achieved, but transition capacitance causes crosstalk and phase shifts at high frequencies
Solution Approach 1:
The patent extracts the problematic optocoupler from the control signal path and replaces it with a capacitor-based coupling mechanism. The control voltage is supplied directly through capacitors C1-C4 to the gates of series-connected MOSFETs, eliminating the transition capacitance and phase shifts introduced by optocouplers while maintaining potential isolation through the capacitive coupling.
Solution Approach 2:
The patent introduces capacitors C1-C4 as intermediary elements between the control circuit and the MOSFET gates. These capacitors serve as mediators that block DC potential differences while allowing AC control signals to pass, thereby achieving potential isolation without the harmful effects of optocouplers. The capacitors act as frequency-dependent intermediaries that enable high-frequency signal transmission.
2Manufacturing precision
If individual operating point adjustment is performed for each amplifier element, then manufacturing tolerances are compensated, but device complexity and adjustment effort increase
Solution Approach 1:
The patent changes the operating parameters by using capacitive coupling to block DC offset voltages from affecting the MOSFET gate voltages. This allows the operating point to be determined by the AC signal characteristics rather than DC bias conditions, reducing sensitivity to manufacturing tolerances. The capacitors C1-C4 effectively reset the DC operating point for each MOSFET, compensating for tolerance variations without requiring individual adjustment.
3Strength
If series connection of amplifier elements is implemented, then breakdown voltage is increased, but voltage distribution uniformity and control become difficult
Solution Approach 1:
The patent uses capacitors C1-C4 as intermediary elements in the control signal path to each MOSFET in the series connection. These capacitors isolate the DC potential differences between series-connected elements while allowing AC control signals to uniformly affect all devices. This ensures that voltage distribution remains uniform across all MOSFETs in the series string, enabling high breakdown voltage operation without sacrificing control uniformity.
4Speed
If bandwidth is increased for high frequency operation, then processing capability is improved, but phase shifts and crosstalk from parasitic capacitances increase
Solution Approach 1:
The patent removes the source of parasitic transition capacitance by eliminating the optocoupler from the control path. By using direct capacitive coupling through C1-C4, the control signal experiences minimal parasitic effects, allowing high-frequency operation with reduced phase shifts and crosstalk. The simplified control architecture enables broader bandwidth without the harmful high-frequency effects that would otherwise limit performance.
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 enhances the breakdown voltage, linearity, reliability, and efficiency of series-connected amplifier elements by minimizing interference currents and maintaining a uniform voltage distribution across the series-connected transistors, thereby improving the overall performance and reducing heat losses.
Implementation Method 1
a voltage divider connected to the buffer input and connected in parallel to the power path, wherein the buffer output is connected to the control input of the amplifier element and the power path of the amplifier element is routed via the current control connection and the reference connection
Implementation Method 2
the buffer input having a high-resistance input impedance relative to the reference connection
Implementation Method 3
the buffer output having a low-resistance output impedance relative to the reference connection
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A hybrid amplifier element (100) is specified, comprising an amplifier element (102) including a control input and a power path, a decoupling unit (101) comprising a buffer input (3), a buffer output (6), a reference terminal (4) and a current control terminal (5), and a voltage divider (Z) connected to the buffer input (3) in parallel with the power path.The buffer output (6) is connected to the control input of the amplifier element (102), and the power path of the amplifier element (102) is routed through the current control terminal (5) and the reference terminal (4), the reference terminal (4) forming a reference potential for the other terminals, the buffer input (3) having a high input impedance relative to the reference terminal (4), the buffer output (6) having a low output impedance relative to the reference terminal (4), a device for linear voltage amplification between the buffer input (3) and the buffer output (6), and/or a device for generating a reference voltage between the buffer output (6) and the reference terminal (4), and a device for influencing the current between the current control terminal (5) and the reference terminal (4) depending on the voltage between the buffer input (3) and the reference terminal (4) are provided.Furthermore, an amplifier circuit (103) with such a hybrid amplifier element (100) is specified. The hybrid amplifier element (100) enables linear voltage amplification into the kV range.