Hot-plugging requires a connector where ground & power connects before data, as in a USB plug. Otherwise in your case you can get a situation where only the 12V and a data line are connected, putting 12V through the Teensy.
Alternatively add...
RS232 might mitigate most of the concerns. Look for RS232 chips which can handle accidental connection to 12V.
You might also consider a PTC fuse on the 12V supply side. They won't protect Teensy from damage, but if something goes wrong in the...
Another concern to consider with hot plugging is the inrush current during connect and high frequency effects (mainly due to self inductance of the wire) at connect and disconnect.
The USB 2.0 spec has an excellent summary of the issues in...
Honestly, I have never tough about this problem before and am now concerned.
Considering a scenario were I can't change the plug for a newer one specifically designed for hot plugging, is there any easy solution to protect the circuit from this...
Nice! So far we have been using just normal 3.3V UART TTL over those 10m wires and it was working normally, while I agree that RS232 or RS485 would be more suitable for the job.
The cables are just regular multiconductor cable, unshielded and...
Thanks for the support!
I will try to incorporate RS-232 on my next circuit design. Right now, it doesn't have the space or connections for the needed RS-232 transceiver, like the MAX3232. I will try to solve the issue with the diodes and the...
Any chance the 4 pin connector could be plugged in backwards by mistake? Or even if it has a shape that can't fully mate backwards, is it possible for the 12V to touch the other pins even briefly if someone tries to plug it in the wrong way?
Does the connector have a design that ensures the ground pins mate first?
Generally when hot plugging you want ground to connect first then power and only then the signals.
If power and your data signals somehow connect before the ground it can...
No, it doesn't. Most of the times, all of them will connect the same time. Depending on the inclination of the plug or if any of the pins are loose, any of them could connect first than the other.
That's a very interesting take. Haven't tough of...
Hi Paul!
The connector has a specific orientation that prevents it from being plugged in any other way. Check the image below:
Even so, after the first Teensy was damaged, I took extra care to plug and unplug the connector the right way and...
I have an application where one Teensy 3.5 (main module) communicates with a Teensy 4.0 (remote module) over a 10 meter wire.
This wire carries the TX and RX signals from Teensy 3.5 Serial6 to Teensy 4.0 Serial1, GND and 12V that powers the...