Teensy 4.1 Ethernet connector + stacking headers question

MichaelMeissner

Senior Member+
I tend to generally put stacking headers on my Teensys, such as this cut down to 24 pins:

I was just idly assembling the components for attaching the ethernet to the 4.1. Note, at this time, I don't have a need for the ethernet, just adding it in case some day I might need it.

Right now, I have the digikey parts, and I should get the OSH park parts by Friday.

I put the 2x3 2mm pitch male pins in my Teensy 4.1, and they fit fine. However, the 2x3 2mm pitch to cable connector won't fit on the Teensy due to the stacking header installed.

If you look on the 4.1 product page, it hangs over: https://www.pjrc.com/store/teensy41.html.

Somebody else had mentioned the following cable available on Amazon:

That too looks like the connector box would over-hang the connection.

I imagine that I could just solder 6 wires onto the ethernet ports, but I've always had problems with wires like that eventually coming dis-connected, and I would prefer a male/female connector that I can plug in and remove as needed.

I don't do much with 2mm pitch connectors, so I don't know what is out there. Is there a female header for 2x3 2mm that is as tall as a normal 2.54mm stacking header, that I could then more easily attach/deattach the ethernet connector.
 
I tend to generally put stacking headers on my Teensys, such as this cut down to 24 pins:
...

Somebody else had mentioned the following cable available on Amazon:

That too looks like the connector box would over-hang the connection.
...

I mentioned getting a set of those ( overly long cables - but premade - and seemed to work ). Indeed the plastic cable holder and restraint overlap the edge pins in the same way as shown on the PJRC page above.

Though desperate hacking might work with super glue on the inside plastic 'snaps' and some good (other) bonding agent on the cross pieces across the cable to allow machining off the outer edge. The cable is pierced in place - and that Amazon unit does have second snap cover to reverse and strain relieve the cable - so it also may be taller.
 
I mentioned getting a set of those ( overly long cables - but premade - and seemed to work ). Indeed the plastic cable holder and restraint overlap the edge pins in the same way as shown on the PJRC page above.

Though desperate hacking might work with super glue on the inside plastic 'snaps' and some good (other) bonding agent on the cross pieces across the cable to allow machining off the outer edge. The cable is pierced in place - and that Amazon unit does have second snap cover to reverse and strain relieve the cable - so it also may be taller.

Yes, any cable where you have to puncture the cable to do the connection, is going to be wider on both sides. From the picture, it looks just like the Amazon part is just the other part where they just mated a fixed size cable. But with the Teensy, you have the problem that the space on the one side is limited. Perhaps you can shave it off and use glue, perhaps not.

Doing a search for 2mm pitch female header found a few headers. Most would have to be cut down, but there is this part (TE AMPMODU 2-1734506-6):

However, the female part doesn't look to be as high as the standard stacking header (7mm). And I suspect the polarizing bump on the side will need to be filed down.

Looking on ebay, I see a 2x10 connector from a USA shipper, that could be cut down on one side:

Or if I needed a bunch of them (not):

Assuming I wanted to wait for delivery from China there is:

Adafruit does sell 10 position, 1 row 2mm headers:

And I see on Amazon, UXCELL makes a header that is taller, but it is 2x5 position, but presumably it can be cut down. However, since its delivery is August, I assume it is from a foreign shipper, and I've had some bad experiences recently with foreign shippers (lost or extremely delayed shipments -- the merchants themselves seem to be ok, but it is the shipping process that is problematical).

Amazon also sells a UXCELL 2x10 position normal sized header that has June delivery:

One of the things that makes this search harder is if I specify '2mm pitch', the search engines think '2.54mm pitch is good enough'
 
Last edited:
yes, a bit pricey.

btw, I've been looking for 2mm 2x3 extra tall riser pin headers but haven't found any yet. If you see any in your searches, please let me know.

And yes, the search engines seem to get confused with 2mm pitch stuff.
 
yes, a bit pricey.

btw, I've been looking for 2mm 2x3 extra tall riser pin headers but haven't found any yet. If you see any in your searches, please let me know.

And yes, the search engines seem to get confused with 2mm pitch stuff.

The Amazon one with UXCELL header (foreign shipper to USA) looks taller, and a similar one from ebay. This is for a 2x5 header. So you would need to cut it down to a 2x3 header:
 
Last edited:
I saw that. Guess I should have been clearer, I want the male kind, not female. Something like this but 2 mm pitch:
0J2350.600x480.jpg
 
I found what I wanted - Samtec. They have a very wide range of connectors for this sort of thing. Have to go through Digikey or Mouser. Look at "Board to Board & Mezzanine Connectors" in Mouser.
 
FWIW, if you order through digikey, the Samtec headers are sent by Samtec and not digikey. Unfortunately in doing the ordering, digikey does not specify what the shipping is.

I ordered headers from mouser, and they had some in stock (not many though). Mouser does not appear to have an option for using the US post office so I can send mail to my PO box.

Where I live, I did not have an official street address for 15+ years, so I get all mail at the PO box. In addition the Fedex/UPS/DHL drivers routinely mis-deliver packages to our neighbors. In normal times, I would just send stuff to my work, but that is inconvenient right now.

It was kind of grating to pay $8 (US) for UPS or FedEx shipping for 4 headers at $1.20.

Here is what I bought: https://www.mouser.com/ProductDetail/200-MTMM10308GD300.
 
Yeah, shipping cost is par for the course. I keep a running list of parts I will be needing so I can avoid the $8.50 for a $0.50 part problem. Mouser used to have a USPS first class option for around $3 but that went away a wile ago. Was nice since most of my orders weigh well less than 16 ozs. Lately, they have upgraded my shipping to 2nd for free so that's nice.

By the way, Mouser does something similar with some Samtec parts. Even though they showed the parts as in stock, they were delayed and ship at a later date (June 9, iirc). Someday I will get them. Now its a race to see which order gets delivered first - OSHPark or Mouser.
 
FWIW, it looks like Mouser has some parts on hand. For the part I choose:

I ordered 4 of the male header pins on Saturday June 6th. Mouser was offering Fedex 2 day shipping for the price of ground shipping, and I selected that.

The headers were sent to Fedex on Monday June 8th, and Fedex delivered it today (Wednesday June 10th) to Massachusetts. I haven't soldered it in just yet, but it looks like the header just barely clears the stacking headers I have on the Teensy 4.1. It looks like pins 21 and 20 can't be used in the stacking header if I have the ethernet connection, but USB host connection on the other side is fine for normal 0.1" (2.54cm) headers. I was able to plug in a 5 pin USB host to USB-B header cable.

So I suspect if you want a fully tricked out Teensy 4.1 with USB host, ethernet, and audio shield, the audio shield will need to go under the Teensy 4.1, Or else you may need to attach permanent jumper cables to bring out the USB host and ethernet.
 
Back
Top