Optical Switch Driver Timing to Reduce Channel Cross-Talk
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dynamic electrical cross-talk between driver channels in optical switches is significant due to shared electrical supply lines, especially when integrating multiple drivers onto a single chip, making it difficult to compensate using position feedback loops.
Innovation Solution
Implementing staggered switching and high-impedance modes for non-switching drivers during voltage transitions, where switching periods are interleaved with no-switching periods, and non-switching drivers are placed in high-impedance mode during switching events to isolate channels from cross-talk.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple driver circuits share the same electrical supply and ground lines, then device integration is improved, but electrical cross-talk between channels increases
Solution Approach 1:
The patent applies periodic action by implementing staggered switching where drivers are activated in alternating periods rather than simultaneously. During each switching period, only certain drivers are active while others remain in high-impedance mode, creating a periodic pattern that reduces cross-talk. This is achieved through a controller that generates switching signals with staggered timing for different driver circuits.
Solution Approach 2:
The patent applies local quality by placing non-switching drivers in a high-impedance mode specifically during their non-active periods. This creates different electrical states for different drivers at different times - switching drivers have low output impedance while non-switching drivers have high output impedance. This localized impedance control reduces the harmful cross-talk effect on a channel-by-channel basis.
2Object-affected harmful factors
If drivers are placed in high-impedance mode during non-switching periods, then cross-talk is reduced, but switching time may increase
Solution Approach 1:
The patent implements periodic switching patterns where drivers alternate between active and high-impedance modes. By carefully designing the period duration and duty cycle, the system achieves cross-talk reduction while maintaining acceptable switching speeds. The periodic nature allows time for voltage transients to settle during high-impedance periods while ensuring drivers are ready to switch again in the next period.
Solution Approach 2:
The patent applies dynamics by making the driver output impedance time-dependent rather than static. Drivers dynamically transition between low-output-impedance mode during switching and high-output-impedance mode during non-switching periods. This dynamic impedance adjustment optimizes both cross-talk reduction and switching performance by adapting the electrical characteristics to the operational requirements at each moment.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An optical switch with a plurality of actuators comprises a controller configured to control the operation of a plurality of channels, where each channel has at least one electrical driver and at least one actuator, by interleaving periods of voltage switching output with periods of no voltage switching output for one or more drivers whilst the output voltage is switching from one level to another level. Alternatively, an optical switch with a plurality of actuators comprises a controller configured to control the operation of a plurality of channels, where each channel has at least one electrical driver and at least one actuator, by switching the output voltage from one level to another level for at least one driver of a first channel whilst at least one oilier driver of at least one other channel is in a relatively high impedance mode.