Maker Pro
Maker Pro

Creating a USB-C Passthrough with power charging detection

StealthRT

Sep 4, 2010
143
Joined
Sep 4, 2010
Messages
143
Hey all I have a project I am needing to do but I'm unsure as to the best way to go about doing it.

What I am wanting to do is check to see if a tablet or laptop is plugged into the USB-c cable so that I can have a visual representation of confirmation that it is connected correctly.

Most of the tablets I am using do not have any visible feature that showcases that its plugged in or not. But even if it did i would never be able to see it due to the tablets being close together.

This is what my setup I created looks like:
enter image description here

When your placing the tablet/laptop into the slots from the front it's difficult to tell if it made it into the connector or missed it.

So my idea was to create a PCB that has 6 female USB-C inputs and 6 female USB-C outputs. But I am not sure what I need to test on the pins to determine if its connected to something or not? I plan on using an arduino to check the voltage and see if it drops XX amount when something is plugged in but again, there may be a better way of checking it?

My PCB would look similar to this one but without the headers and holes and with more than one set: enter image description here
 

Harald Kapp

Moderator
Moderator
Nov 17, 2011
13,337
Joined
Nov 17, 2011
Messages
13,337
Checking for voltage alone is going to be unreliable at best, won't work at all in most cases.
You'll have to measure current. Insert a small so called sense resistor into the VCCline and measure the voltae drop across the resistor. When the tablet is inserted correctly and is charging, the current will develop a measurable voltage drop across the resistor.

Less invasive would be the use of a current sensor.

Of course all this works only as long as the tablet is charging. When the tablet's battery is fully charged, charge current will drop to zero and the current measurement will be the same as with no table present. You may want to add a small pushbutton to detect the physical presence of the tablet.
 

StealthRT

Sep 4, 2010
143
Joined
Sep 4, 2010
Messages
143
Looks like this is a charging only station. No data connections required?
Yes no data would be needed. Only power.

I was thinking today that I could use a limit switch in each decider for the tablet/laptop to hit causing the signal that it’s charging but that doesn’t really tell me it’s connected correctly and is actually charging.
 

StealthRT

Sep 4, 2010
143
Joined
Sep 4, 2010
Messages
143
So something like this?

image-6-450x312.png

2023-04-22-22-02-43-Model.png

2023-04-22-22-08-14-The-USB-Type-C-Connector-A-Brave-New-World-for-the-PC-Industry.png
 

Delta Prime

Jul 29, 2020
1,203
Joined
Jul 29, 2020
Messages
1,203
But what's going to happen when you need a TV tray for salisbury steak Frozen TV dinner?:confused:
You have to sacrifice one TV tray to make a backing
photo_1682219862612.png
 
Top