60 GHz Clock Distribution Network Using Composite I/Q Clock Routing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The design of 60 GHz transceivers requires significant area on semiconductor dies due to the use of transmission lines for clock distribution, leading to power dissipation and increased real estate usage, and existing power amplifiers struggle with minimizing second harmonics that distort the signal.
Innovation Solution
The use of lumped capacitors and inductors to form power dividers and quadrature hybrids instead of transmission lines, combined with a composite 60 GHz clock waveform and a Class-E amplifier tuned to pass only the fundamental frequency, reduces area usage and power dissipation while minimizing second harmonics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If transmission lines are used to distribute 60 GHz clock signals, then the clock distribution function is achieved, but the area occupied by the distribution network increases significantly
Solution Approach 1:
The patent replaces transmission lines (electromagnetic field-based distribution) with lumped element circuits (discrete electrical components) for clock signal distribution. This substitution dramatically reduces the area required for the distribution network while maintaining proper clock signal delivery to all circuit components.
Solution Approach 2:
The patent changes the operating parameters by using lumped element LC circuits tuned to resonate at the clock frequency instead of distributed transmission lines. This parameter change enables compact implementation of clock distribution functionality that previously required large transmission line structures.
2Use of energy by stationary object
If transmission lines are used for clock distribution, then clock signals can be routed, but power dissipation increases due to interconnect requirements
Solution Approach 1:
The patent substitutes transmission line-based clock distribution with lumped element circuitry, eliminating the need for extensive interconnect routing. This substitution reduces power dissipation associated with signal transmission through long interconnects while preserving complete clock distribution capability across the circuit.
3Manufacturing precision
If transmission lines are used to maintain 90° phase separation between in-phase and quadrature clocks, then phase accuracy is preserved, but layout complexity increases
Solution Approach 1:
The patent replaces transmission line phase management with lumped element quadrature generation circuits. This substitution maintains precise 90° phase separation between in-phase and quadrature clock signals while dramatically simplifying the physical layout, as the phase relationship is generated electrically rather than enforced through geometric transmission line arrangements.
4Power
If conventional power amplifiers are used, then signal amplification is achieved, but second harmonics distort the output signal
Solution Approach 1:
The patent converts the harmful second harmonic distortion into a beneficial feature by deliberately generating strong second harmonics that are then used to drive a Class-E amplifier. The Class-E amplifier's load network is specifically designed to suppress these second harmonics at the output while allowing them to exist internally, thereby eliminating distortion rather than treating it as a defect.
Solution Approach 2:
The patent changes the operating parameters of the power amplifier by transitioning to Class-E operation with specific load tuning. This parameter change enables the amplifier to efficiently suppress second harmonics at the output frequency while maintaining high power amplification capability, transforming the amplifier's behavior from conventional to harmonic-suppressing operation.
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 approach decreases insertion loss and area usage by up to 80%, reduces power dissipation, and enhances signal purity by minimizing second harmonics, allowing for more efficient energy transfer to the antenna without increasing output power or signal bandwidth.
Implementation Method 1
The use of lumped capacitors and inductors to form power dividers and quadrature hybrids
Implementation Method 2
The use of lumped capacitors and inductors to form power dividers and quadrature hybrids
Implementation Method 3
a Class-E amplifier tuned to pass only the fundamental frequency
Data Source
AI summary
Herein is presented, a low power on-die 60 GHz distribution network for a beamforming system that can be scaled as the number of transmitters increases. The transmission line based power splitters and quadrature hybrids whose size would be proportional to a quarter wavelength (˜600 μm) if formed using transmission lines are instead constructed by inductors/capacitors and reduce the area by more than 80%. An input in-phase I clock and an input quadrature Q clock are combined into a single composite clock waveform locking the phase relation between the in-phase I clock and quadrature Q clock. The composite clock is transferred over a single transmission line formed using a Co-planar Waveguide (CPW) coupling the source and destination locations over the surface of a die. Once the individuals the in-phase I and quadrature Q clocks are required, they can be generated at the destination from the composite clock waveform.