eUSB2 Repeater EOP Hold Circuit for Noise-Free Level Shifting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The implementation of eUSB2 repeaters faces challenges in detecting the end of a USB packet (EOP) indicator accurately, leading to noise transmission due to hub switching skews, especially when conventional USB and eUSB2 systems operate at different voltage levels, and existing solutions like CDR circuits and PLLs are large and power-consuming.
Innovation Solution
A circuit that includes amplifiers, comparators, and a logic circuit to detect the idle state of eUSB2 differential input signal lines, maintaining the last bit of the EOP indicator for up to four additional bits to prevent noise, without using a CDR circuit or PLL, thereby enabling level-shifting between eUSB2 and USB voltage levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional CDR circuits and PLLs are used to detect EOP indicator, then detection accuracy is improved, but device size and power consumption increase
Solution Approach 1:
The patent extracts the essential detection function from complex CDR circuits and PLLs by using only a comparator to detect voltage level transitions. This removes unnecessary components while retaining the core capability of detecting EOP indicators, thereby reducing device size and power consumption while maintaining detection accuracy.
Solution Approach 2:
The patent replaces expensive, complex CDR circuits and PLLs with a simple, low-cost comparator circuit. The comparator is a basic electronic component that consumes minimal power and occupies minimal space, effectively substituting for the complex synchronization circuits while achieving the same detection function.
2Measurement precision
If conventional CDR circuits and PLLs are used to detect EOP indicator, then detection accuracy is improved, but power consumption increases
Solution Approach 1:
The patent extracts the essential detection function from power-hungry CDR circuits and PLLs by using only a comparator. This removal of unnecessary circuitry directly reduces power consumption while preserving the critical EOP detection capability, addressing the energy efficiency requirement for portable devices.
Solution Approach 2:
The patent substitutes complex, high-power synchronization circuits with a simple comparator that consumes minimal power. This replacement achieves the same detection function with dramatically reduced energy consumption, enabling deployment in battery-powered portable devices.
3Device complexity
If hub switching skews are not compensated, then device complexity is reduced, but noise transmission increases
Solution Approach 1:
The patent applies preliminary action by holding the differential output signal at its final logical value for a predetermined period after detecting the EOP indicator. This pre-emptive measure ensures that any subsequent hub switching skews or noise on the input lines do not propagate to the output, effectively preventing noise transmission without adding complex compensation circuits.
Solution Approach 2:
The patent applies preliminary anti-action by actively suppressing potential noise transmission through the bus holder circuit. By holding the output signal steady after EOP detection, the circuit preemptively counteracts any harmful effects from hub switching skews or input line noise, preventing them from reaching the output before they can cause interference.
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 effectively prevents noise transmission by accurately identifying the end of the EOP indicator, ensuring compliance with USB specifications while reducing the size and power consumption of the eUSB2 repeater, making it suitable for smaller, lower-power environments.
Implementation Method 1
a first amplifier having a first input coupled to a first node, a second input coupled to a second node, a first output, and a second output
Implementation Method 2
a first comparator having a first input coupled to a seventh node, a second input coupled to an eighth node, and an output
Implementation Method 3
The bus holder circuit has an input, a first output coupled to the third node, and a second output coupled to the fourth node
Implementation Method 4
a third amplifier having a first input coupled to the third node, a second input coupled to the fourth node, a first output coupled to a fifth node, a second output coupled to a sixth node
Data Source
AI summary
Aspects of the disclosure provide for a method. In at least some examples, the method includes receiving, at a circuit, data via a differential input signal. The method further includes detecting a falling edge in the data received via the differential input signal. The method further includes holding an output of the circuit at a final logical value of the data. The method further includes disabling a transmitter of the circuit while holding the output of the circuit at the final logical value of the data. The method further includes releasing the output of the circuit from the final logical value of the data.