Trying to find a USB connector with sensor spring/pin - Page 1
Forum section: electronics / general

author: newbadboy
author_rank: Regular Contributor
timestamp: April 28, 2017, 06:11:13 am
content: As topic i'm trying to find a Usb connector with a sensor pin such as mounted on SD card holders. A spring which can detect if a connector is connected or not. I have found one but it's a standing and i prefer one standard mounted SMD.https://electronics.stackexchange.com/questions/215755/special-usb-port-with-sensor-contacthttp://portal.fciconnect.com/Comergent//fci/drawing/73725.pdfPls help me.

author: Jeroen3
author_rank: Super Contributor
timestamp: April 28, 2017, 07:28:33 am
content: This seems redundant. USB already has this in timeouts and voltage levels on the data lines.It feels like you're using the USB connector for non-USB business?

author: newbadboy
author_rank: Regular Contributor
timestamp: April 28, 2017, 09:09:34 am
content: Both yes and no. Unfortunatly i cannot say to much about what i'm trying to do at this state

author: cowana
author_rank: Frequent Contributor
timestamp: April 28, 2017, 09:47:33 am
content: I spent a while trying to find the same thing - my application was to give my bench power supply a USB output, which automatically switches to 5V output (and enables the over-voltage protection at 5.5v) when a USB lead is connected (regardless of whether it is plugged into a device or not).That FCI connector you linked to was the only one I could find in my searching - however I'd love to know if they are available from any other manufacturers (especially if you can get them in other orientations).

author: newbadboy
author_rank: Regular Contributor
timestamp: April 28, 2017, 01:21:42 pm
content: Shit, well i let you know if i find something.

author: grifftech
author_rank: Frequent Contributor
timestamp: April 28, 2017, 07:04:49 pm
content: have a sliding cover over the port that activates a switch when open.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 29, 2017, 12:47:26 am
content: Probably the biggest use case are USB battery packs that automatically turn on when there is something plugged in.

author: aargee
author_rank: Frequent Contributor
timestamp: April 29, 2017, 02:34:05 am
content: If it's not part of the USB standard, then finding what you want may be a case of build your own non-standard device.

author: Ampera
author_rank: Super Contributor
timestamp: April 29, 2017, 04:30:25 am
content: Does it have to be USB? Maybe DIN could be a better option as you can just have a pin to register if the device is connected.Speaking of DIN, why don't we use it anymore? I love the DIN connectors. My only issue with it is the name. I wish we didn't have to either call it DIN to confuse everybody, or to call it by the DIN number to make it even more confusing.

author: 1audio
author_rank: Frequent Contributor
timestamp: April 29, 2017, 04:57:11 am
content: Microusb has an extra pin normally for OTG but easily hijacked for other tasks.Sent from my LG-H811 using Tapatalk

author: newbadboy
author_rank: Regular Contributor
timestamp: April 29, 2017, 01:57:51 pm
content: Well, it's hard to explain without reveiling to much.But yes it is connected to usb ports. Making own slider and so is possible but not realistic. It's intended to go on crowdfunding if it will work as i hope.Basically i want to detect if something is connected and disconnected to a usb port. And without any really intelligence such as controller. Measuring logical levels and such is ok but not more.Also it's important that detection is done really early att connection/disconnection. Before any real data traffic i sentDo you guys have any ideas?

author: jpc
author_rank: Unknown
timestamp: April 29, 2017, 02:49:33 pm
content: Are you powering it from the USB port you plug it into or is it self powered.

author: dgtl
author_rank: Regular Contributor
timestamp: April 29, 2017, 02:55:27 pm
content: The device detection protocol of the USB is pretty trivial. The host side has very weak pull-down resistors. The device pulls up with a resistor either D+, D- or both (depending on what speed it wants to use). The host side sees that both lines are not low anymore.On the device side, you can just verify the presence of the vbus power.

author: newbadboy
author_rank: Regular Contributor
timestamp: April 30, 2017, 08:17:54 pm
content: It's powered by vbus. Thx ill look into it

author: aandrew
author_rank: Frequent Contributor
timestamp: May 02, 2017, 04:48:25 pm
content: Quote from: NiHaoMike on April 29, 2017, 12:47:26 amThis can already be done by sensing current on the D+/D- lines (and in fact is required if you are complying with the battery charge spec on usb.org).

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 03, 2017, 02:34:07 am
content: Quote from: aandrew on May 02, 2017, 04:48:25 pmThe device detection has to work with practically zero standby current (including no voltage applied to the USB port in the off state) and work regardless of whether or not the device does anything with the data lines.One USB battery I have uses an extra contact that the outside of the USB plug shorts to ground. That triggers the boost converter to turn on. The interesting part is that there's a small microcontroller measuring the output current and switch off the output when the output current falls in a manner that suggests a connected device has finished charging, but is pretty resistant to false triggering by USB devices that directly use the USB power. (It appears that a long duration of nearly constant current draw is one of the preconditions.)