Resonant Transmit Receive Switch Using Single LC Resonator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing resonant switches in radio front ends require two resonators, occupying more semiconductor surface area and using high breakdown voltage devices to handle high voltages, making integration with low breakdown voltage transceivers and power amplifiers difficult and costly.
Innovation Solution
A resonant switch using a single inductor-capacitor resonator and semiconductor transistors with low breakdown voltage, implemented using standard 0.13 um CMOS processes, with three switching devices to control impedance and voltage drops, allowing integration with low breakdown voltage devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high breakdown voltage devices are used to handle high voltage from power amplifier, then voltage handling capability is improved, but integration difficulty and cost increase
Solution Approach 1:
The patent introduces an intermediary resonant circuit (inductor-capacitor network) between the power amplifier and the switching device. This resonant circuit acts as a voltage mediator that limits the voltage seen by the low breakdown voltage transistor while still allowing high power transmission. The resonant circuit transforms the high voltage from the power amplifier into a form that the low breakdown voltage device can safely handle.
Solution Approach 2:
The patent changes the operating parameters of the resonant circuit to control voltage levels. By adjusting the resonant frequency and impedance of the LC circuit, the voltage seen by the switching device is limited to safe levels while maintaining the ability to handle high power. The resonant circuit transforms voltage parameters dynamically based on operating conditions.
2Reliability
If two resonators are used in transmit and receive paths, then switching performance is improved, but semiconductor surface area increases
Solution Approach 1:
The patent designs a single resonant circuit that serves multiple functions: it operates as the transmit path resonator when the transmit switch is closed, and as the receive path resonator when the receive switch is closed. This multi-functional design eliminates the need for separate transmit and receive resonators, reducing the overall semiconductor area while maintaining switching performance.
Solution Approach 2:
The patent merges the transmit and receive resonators into a single shared resonant circuit. The same inductor-capacitor network is used for both transmitting and receiving operations, with the appropriate switches being activated based on the desired mode. This consolidation reduces component count and semiconductor area.
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
The solution provides improved resistance to high voltage breakdown, enabling efficient integration with transceivers and power amplifiers, reducing semiconductor area usage and costs while minimizing voltage exposure to switching devices.
Implementation Method 1
the inductor and capacitor form a resonant circuit when the first switch is closed
Data Source
AI summary
A device having a radio front end is provided. The radio front end includes an inductor having a first end and a second end. A capacitor having a first end and a second end is connected to the second end of the inductor. An antenna is connected to the second end of the inductor and the second end of the capacitor. A first switch is connected to the first end of the inductor and the first end of the capacitor, wherein the inductor and capacitor form a resonant circuit when the first switch is closed. A second switch is connected to the resonant circuit, the second switch connecting the resonant circuit to ground through a low impedance when the first switch is closed. A third switch is connected to a transmit power amplifier connecting the transmit power amplifier to ground through a low impedance when the first switch is closed.