Make a USB OTG Host Cable. the Easy Way!





Introduction: Make a USB OTG Host Cable. the Easy Way!

About: My name is Taylor, I am an electrical repair tech by day and an engineer by night, after work or free time.

I have been in the market for an OTG cable, otherwise known as a host cable for some time and I have found that the only places that seem to sell them are online only. This is not a problem half the time. I tend to do a fair amount of online shopping but for this product I was left looking for an alternative. Some sellers sold them cheap while the wait time could be as high as 30 days and others sold them for a lot more than what they are worth while the wait time was 2 days. I was looking for a middle ground. When I say a lot more I really mean you are paying more for the product than what it's worth. For those of you who don't know what a USB OTG (on the go) host cable is, it is a simple modified USB cord that has a female (most of the time) USB port on one end and a micro male USB on the other end. The types of connections on each end can differ. This cord acts as a USB port for your phone or tablet and it enables you to use external devices such as a keyboard or mouse via the female USB connector on your phone. This cord is a must have for those who want the most out of their smart phone or tablet. It works by connecting an unused pin in the micro end, to ground. Like I said it is a simple modification. Some phones and tablets do not support this function so it is wise to search the web to find if your device is compatible with this function. I explained a little as to why I was looking for an alternative to buying one online and let me go a little more in depth as to why I chose the DIY route. The top two reasons are, it would be cheaper and I wouldn't have to wait for it, You can make one for under 2 dollars with stuff you more than likely have lying around your house!

With my cable I can now use a keyboard, an xbox 360 controller and flash drives on my galaxy note 2 without any rooting. I can also use mice and other USB hardware.

Step 1: What You Will Need

You will need a Micro USB cable (in my case), a USB female port (took one off an old charger), a hobby knife, solder and hot glue and about 30 minutes of your time.

Step 2: Cutting Into the USB Micro End and Making It a Host

I used a cheap dollar store USB cord and I'm glad I did. The cheaper the cord the easier it is to cut and mod. Take a hobby knife and carefully cut the seam and pry back the rubber. Then You can remove the USB micro male connector. You can cut it off or you can work within the wire. After You can see the micro USB connector you have to take it apart to reveal the 5 pins.There is a metal case around the pins that make the shape of the connector. Mine had an easy clasp that I lifted with my knife then slowly removed. Once you see the 5 pins you have to solder the pin next to ground to ground. A little solder bridge is all that is needed. If you don't know the pinout you can look at the picture I included or you can go by the color coded wire. There are four wires inside a normal USB cord and the colors are red, black, white and green. These colors help identify their connection. Red is 5volt+, black is Gnd -, white is data - and green is data +. Some cords use different colors but the connections can still be identified by using the image to help with pin out. The picture I included has the pins numbered, 1 is red 5 volts+, 2 is white data -, 3 is green data +, 4 is not used unless its an OTG cable and 5 is Gnd, black. You have to connect pin 5 to 4. When pin 4 is connected to pin 5, Ground, it allows a pass through that enables your phone to use external devices. That is all that is needed to turn your micro USB into a host cable. After pin 4 and 5 are soldered together you can place the metal case back on and give it a quick test. I tested mine on an old phone before using it on my note. Once you plug it into your phone you should get a message saying "usb connector connected' or something similar. You don't even have to have anything connected to it to get that message. If you removed the wires to mod the pins you can solder them back onto the connector and move to the next step

Step 3: Adding a Femal USB Port.

In order to give you the option of using this as a USB port you need to add a female USB port to the other end of the cable. My cable had a male connector so all you have to do is replace that with a female connector. I also decided to shorten the cord for ease of carry. Simply cut off the male connector, strip and tin the four wires and solder them to the USB female port. Follow my picture for correct wire placement or search for the pinout.

Step 4: Insulate and Make It Stronger

By now your cord is complete but in order to increase the life time of the cord you want to strengthen the wires and connections with some hot glue and electrical tape and you are finished!

I hope you enjoyed and thanks for reading!

5 People Made This Project!


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48 Discussions

Would it be a similar process for the iPhone cable?

Very useful and informative, thank you. I just converted a £0.50 micro USB 10cm extension cable to OTG and it works perfectly for attaching accessories to my Galaxy Note II.

I just started using VRidge for using my G3 as VR screen.
For this I use USB tethering from the phone to the PC. Would it be possible to splice a wall charger into the data cable so the phone gets charged at the same time?
I was thinking that connecting the charger cable in parallel would work?
Red to red for example. At least then I could use my phone in VR and have it charging from the the same time.

Hi friends, I have an ipad mini and since it's almost full in memory, can i just use the OTG usb female host cable adapter to transfer my photos and videos to into my hard disk? thank you :-)


1 year ago

I am trying to make one but the wires are as follows- two bare wires(silver), two red wires, white and green. And I am confused which one is vcc and which is gnd

can i splice the cord and connect the two wires ?

My company (Shenzhen Hinsung Electronics Co., Ltd.) can make USB OTG Cables with USB Power ( They are cheap and high quality. And our delivery time is within 15 days. Does anyone have interest in reselling our OTG cables?

12 replies

Sorry to reply you so late. Do you have an email adress?

Yes, here in Southern California Orange County.

If you need an independent rep here, send me the particulars to and we can arrange a dialog.

Thank you,
S. Tito Bombaci

Sorry to see your reply so late.

Do you need me to send you the particulars?

Please contact me if you need. :)

My email is

Is there an OTG for the 40pin adapter for an ASUS Transformer?

I've tried to make and otg with power but can't seem to figure it out. I ran the 5volts positive in parallel with the otg positive and ground. and had no luck. any suggestions?

This is what I would do: So when you have micro usb otg to the phone (which I call A for now), female usb to connect your device (usb drive, mouse etc) to(call B for now) and male usb to get the power from (call C for now). I would make the following connections A to B as described in this instructable but cut the 5V line between A and B, then connect the ground from C to B (and so automaticly also A) and the 5V from C to B, in that way all grounds are connected, data goes between A and B, and the power for your device at B will be taken from the 5V line of C and back to both grounds.

If you would be so kind as to draw a simple sketch to help illustrate your point I would be appreciative. I think I understand your point.

If you're saying just add 5 volts or an external power supply to the micro usb with host. That simply won't work. I've tried. Now I have been reading up on this an apparently you need a specific resistance between sense and ground to acheive both.