Tutorial: How to make an USB OTG adapter

Well this walkthrough was made with one thing in mind there are a lot of USB OTG's out there but why not make my own just for the fun of it. It is cheaper, I personally like to solder so it should be fun.

Excuse me for the inconsistency's in this walk-through, there will be some being my first tutorial of this kind.

To explain a little about the idea behind this extension of your mobile phone. USB On-The-Go, often abbreviated USB OTG, is a specification that allows USB devices such as digital audio players or mobile phones to act as a host allowing a USB flash drive, mouse, or keyboard to be attached.

Lets start off with what you will need for this little and pretty simple project:

  1. Parts wise you don't need much:

- a male micro USB B port, there are many models out there with different kind of connections for soldering.

- a female USB port, I was fortunate enough to find the kinds that are made to be fitted on wire, this is ideal you will see why later;)

- and a piece of cable  with 4 wire's inside a few centimeters long should be enough.

- a small piece of heat shrinking tubing

Next you will need a few tools so you can get things rolling.

2. Easy stuff any of you guys that like to make stuff like this should have around the house.

- first and most important a soldering iron, should have a decent tip the connections on the micro USB port are delicate.

- cutter or exact-o-knife you will need this to get the isolation off the wire and cut the heat shrink tubing.

- solder

- soldering paste, flux, rosin whatever you wanna call it

- tweezers

- lighter

- third hand holder - this is not a must but it's usefull when you need an extra hand

Getting that all of that in order and having everything in arms reach. PS don't forget patience and a little Soda Pop would be nice.

NOW WE CAN START.

3. There are a few images around the web that cover the connection issue wich wire goes on what connection in the specific port. I found some images and put them together to make the process easier. 

This is the sketch that shows how the connections should be made to the usb ports so we get a OTG adapter.

USB 1.x/2.0 standard pinout

Pin	Name		Description
1	VBUS		+5 V
2	D−		Data −
3	D+		Data +
4	GND		Ground

USB 1.x/2.0 Mini/Micro pinout

Pin	Name		Description
1	VBUS		+5 V
2	D−		Data −
3	D+		Data +
4	ID		Permits distinction of host connection from slave connection * host: connected to Signal ground * slave: not connected
5	GND		Signal ground

These are the connection for the two ports, we are going to use Type A USB (the one we have is a female and the one ilustrated is a male, so keep in mind) and the Type B Micro USB ( both male so no problem here)

  4. First of all you will see some inconsistency's in this walkthrough excuse me again but this is my first.:P

First thing you will have to do is strip the cable into individual wires.

Next you will have to strip the endes enough to solder them to the female USB port.

Dip them into flux and put a little solder on them, this will help you get a better connection and without heating the ports to much.

5. Well this is how it should look after we stripped the wires (in my case stripping the wires will help because I have the casing of the female usb port, where i will hide all the fires;) ), if you do not have such a port i do not recomand stripping the wires completely.

 6. After installing the covering for the female USB port we can start and solder the Wires to the micro USB port, don't worry you will just have to solder the wires on the 1,2,3 and 5 pin for now. 7. After that you will have to make a jumper as shown in the pictures above, I made mine from a resistor wire. No biggy, you will just have to make it from pin 5 to pin 4 of the Micro USB port.

This is a close up of the jumper soldered to pin 5 and 4.

 8. Next step to our little project is to get everything inside the housing of the female USB port to the point when only the male Micro USB port is hanging out so we can shrink wrap it. Cut a larger piece of heat shrink tubing than what you need the excess will be cut later. There is nothing much to explain than show you some self explenatory pictures of the next steps you will have to do.

9

Voila your own little heat shrinked USB OTG Adapter.