I know that similar questions have been asked before. I just want to get a better understanding of some details. Please bear with me.
I learnt that I could use an analog CMOS switch or some other dedicated bus switches such as a multiplexer to 'switch off' a segment of a bus. Now I wonder: when a switch is in the 'off' state, will the switch itself contribute to the bus capacitance? If it does, how significant is the influence? is there any way to switch off a part of the bus and completely remove its influence(including the switch) on bus capacitance ?
My application requires a large amount (could be over 400) of I2C devices connected to the bus. However, only 2 or 3 need to be online at any moment. I think the 400pF (or 3000pF when using a buffer?) capacitance limit is the main concern here. I believe a cascade structure of bus switches could solve the problem, but I need the system to be modular which means that each device are equipped with a switch and no cascade structure.
Pardon me if I'm not making this clear. This is my first time asking questions here. Thanks!