What's the connector used to terminate a keyboard wire called?

Do you have a question? Post it now! No Registration Necessary.  Now with pictures!

Threaded View

I have a USB keyboard with a defective cable (i'm retaining the USB-A  
connector). I'm replacing it with a normal cable from a PS2 which i need  
to solder to the USB-A plug/connector. What you are seeing is the opened  
keyboard-PCB connector and PS2 connector (internal that;s plugged into  
it). I want the name of the white connector (it's a 5 hole female  
rectangular thingy) that plugs into a male 5-pin/needle connector that's  
soldered on to the keyboard pcb

Re: What's the connector used to terminate a keyboard wire called?

On 7/9/2016 8:38 AM, Veek. M wrote:
Quoted text here. Click to load it

Looks to be a standard IDC connector such as one would find for a USB  
connection on a motherboard. One would have to measure the pin spacing to  
be more certain. They can be either white or black and the color doesn't  
really mean anything. If you don't have the proper crimper and experience,  
it might be easier to buy a short cable with the proper connector and then  
splice into that. Here is an example of a ready-made cable:


or you might have an unused example inside your computer -- sometimes there  
are connections provided that are not used (but it might take a bit of  
nerve for a novice to start cutting cables, even unused ones, inside a  
computer case).

Re: What's the connector used to terminate a keyboard wire called?

Veek. M wrote:
Quoted text here. Click to load it

Examine the connector and see if it can be reused.

A wire connector like that (wire to board), can use
crimp pins. There is a tiny spring tab on each pin,
which holds it into the box. If you depress the spring
tab (visible through a tiny window in the plastic),
you can pull the wire and pin backwards and out of the
connector body.

Make a drawing of the pin one indicator, and the color
of each wire, before you begin. Or take a few digital
camera photos, so you get the wire order correct. If
you put the colors in the wrong holes, you'll blow
up something.

Page 33 top left, shows a wire connector with 0.1" contact
spacing. The crimp pins that fit into the connector,
are purchased separately and are shown next to the plastic
bit. This picture will illustrate a tiny bit, the parts
of the connector. The left hand side of the connector
pin, has a 45 degree slope, and that's what contacts
the male pin it is mating with. The middle crimp and end
crimp hold onto the wire. I don't even have the right
tool to crimp those, but that hasn't stopped me from using
needle-nose pliers to finish the job. I believe the middle
crimp is for the wire, the end crimp can grip the plastic
insulation, but I use both crimps for the wire itself. And
don't bother building strain relief of any sort.


The back of the connector has a bigger aperture than
the front (that plugs in). The front will have a square
hold, only a little bigger than the dimensions of the
pin. The back hole, where the pin and wire enter the
body, is much larger.

Sometimes stuff like this is hot molded, and impossible
to recycle. And I cannot tell if that's how they made
yours or not.

Best guess,

Re: What's the connector used to terminate a keyboard wire called?

Veek. M wrote:

Quoted text here. Click to load it

Won't work UNLESS the keyboard has builtin circuitry to perform
automatic hardware protocol switching.  You cannot plug a USB-only
keyboard into a PS/2 port (unless you buy an active converter which
costs more than getting a new keyboard).  

USB and PS/2 use *different* hardware protocols.  A PS/2 only keyboard
won't communicate using the USB hardware protocol to a USB port.  A USB
only keyboard won't communicate using the PS/2 hardware protocol to a
PS/2 port.  You would need a USB+PS/2 keyboard that has builtin
auto-detect circuitry to support connecting the keyboard to either USB
or PS/2 ports.  You cannot simply rewire the cable nor will a passive
USB-to-PS/2 dongle work.  Either the hardware protocol conversion
circuitry has to be inside the keyboard or you get an active converter
to which the keyboard connects.  

USB has 4 lines: data+, data-, power (5V), and ground.  Differential
data signaling is used to eliminate induced noise (EMF).  See:
http://pinouts.ru/Slots/usb_pinout.shtml .

PS/2 has 4 lines: data, ground, VCC (5V), and clock.  There are 6 pins
but 2 are unused (there is a dual-PS/2 version where the unused pins get
used for data2 and clock2).  You can already see the differences in the
signaling.  See http://pinouts.ru/Inputs/KeyboardPC6_pinout.shtml .

You never mentioned the brand and model of the keyboard.  If it is a
USB-only keyboard, no rewiring job is going to make it work on a PS/2
port (unless you also rewire the PS/2 port to effectively continue use
the USB hardware protocol but with mismatched connectors).

I'm not clear if you are trying to use a PS/2 connection with your USB
keyboard or if you merely clipped the cord from a PS/2 cable and intend
to use just the wiring to solder it onto both a USB-A connector and onto
the keyboard's PCB.  Seems a neater and easier job to just get a USB
cable, snip off one end leaving the USB-A end, and solder the cable onto
the same spot at the connector inside the keyboard.  Electrically the
connector is superfluous: it was used for assembly requirements.  Or you
could leave the connector inside the keyboard, snip its wires about 2
inches out, slide on some heatshrink tubing over each wire, and solder
splice the USB cable onto the leads from the connector, and then heat
the heatshrink tubing.  The splice job would be hidden inside the

If you absolutely must have a primo wire job (no splicing), DigiKey has
lots of connectors.  The problem is that you won't have the crimp tool
to attach wires to the pins that go into the connector.  Soldering would
have to be delicate so it doesn't enlarge the backend of the connector
pin to prevent it sliding into the connector.  A needle nose plier could
be used for crimping but it's a sloppy method, especially when you
decided to get the connector to do a neat job.  

Re: What's the connector used to terminate a keyboard wire called?

Veek. M wrote:

Quoted text here. Click to load it
Quoted text here. Click to load it

Thanks guys - got it working - awesome replies.

Site Timeline