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USBLC6-2SC6 - Is it possible to connect pins 1 + 6 (and 3 + 4) on the PCB?

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niconiconi:

--- Quote from: tooki on October 19, 2022, 07:25:55 pm ---
--- Quote from: Tarik on October 19, 2022, 02:49:15 pm ---I use a USB connector for IIC because it is an connection between the Arduino board and the external sensor board.
USB connections are reliable, shielded, connectors are cheap and easy to solder
Anyway, I am on open for different ideas ;)

--- End quote ---
There’s a very simple reason why you should never use USB connectors for anything other than USB: people WILL connect USB to it. USB power is 5V. What happens to your 3.3V circuit when 5V is applied?

No, really. Choose something else.

--- End quote ---

+1. Don't abuse customer electronics connectors. If you must abuse the USB connector, at least use some tricks to ensure the device cannot be destroyed. For example, change the power input specification of your board from 3.3 V to 5 V, and use a 3.3 V regulator at VBUS. A 100% duty cycle buck converter sounds like an even better choice. Then to protect the signals... USB uses either 3.3 V (LS/FS) or LVDS (HS) signaling for D+/D-, so this voltage is safe for I2C. You don't need to do anything else. But if you want another signal, change the USB connector to USB 3.0 instead of USB 2.0, and use the two SSRX+/- pins. SSRX is driven by the host to the device, and it's AC-coupled with no DC flow. So it should be safe to plug into a computer.

Tarik:
USB 2.0 doesn't seem to be in your favor because it's too tempting to plug the other end into a computer? Hmm. I have never evaluated this kind of impact of USB :o
Originally, I had also considered using LAN connectors, e.g. a 1 m patch cable.
But that seemed somehow like overkill, also because the short patch cables are not shielded.
If I understood you correctly, the suggestion is to use USB 3.0 and the (DC-free) SSRX pins.
Sounds reasonable  ;D

tooki:
LAN patch cables exist in shielded types. It’s up to you what you buy. (Not that I2C is likely to need shielding.)

While using a USB-C connector makes it easier to avoid damage, I still wouldn’t use it, because users will think it’s USB when it’s not.

An RJ-11 or RJ-45 jack works, or something like DIN or mini-DIN.

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