Electronic Component- 9V to Barrel Jack Adapter

A 9V to Barrel Jack Adapter is an adapter which transfers the 9 volts from a battery to a DC power plug- which then can be plugged in and power a DC power barrel jack with 9 volts.

To use this device, a user just connects a standard 9-volt battery to the 9-volt battery holder slot of the adapter. When inserted correctly, the battery's voltage will be transferred to the DC power plug.

This DC power plug can then be plugged into any DC power barrel jack (of equivalent size). The DC power barrel will then supply 9 volts to the circuit to which it is connected.

This is very handy for any type of circuit where you want to supply 9 volts to the circuit and you want it to operate on battery power, or if you just don't have a standard 9-volt power adapter.

This setup with a 9V to Barrel Jack Adapter can be used to power your own custom-made circuit in which you power it with a DC plug plugged into the DC barrel, or it can be used to power boards with DC power barrel jacks installed into them. Many boards have DC barrels, including arduino boards, parallax boards, and many others.

Above is an example of an arduino board which comes with a DC power barrel jack installed. With this jack, you can insert the DC plug of the adapter and power the board with 9 volts for any various applications.

This part is available through a number of different vendors including www.sparkfun.com.

Ideas for Electronics Projects

Variations of DC Barrel

This 9V to DC plug adapter can also be placed into some dynamic DC barrel jacks for more complex circuits, that possess more functionality.

Solarbotics offers a number of dynamic DC barrels which this adapter can be plugged into for greater circuit functionality.

Both are shown below:

These barrel jacks allow the power from the 9V to barrel jack adapter to be turned on or off. That is, the 9 volts from the battery can be turned on or off by the switch on the barrel jack. The barrel jack on the left uses a rocker switch to swith on and off power, and the one on the right uses a slide switch to turn on or off power.