Introduction: Connecting a Power Switch to Creator Ci40

Building the Creator Ci40 board into an enclosure may require controlling the power to the board remotely. This instructable looks at how to add passive and active options for controlling the DC power supply to the board.

What you'll need

1 x Creator Ci40 board

1 x rocker switch

Some wire

You can purchase a Creator Ci40 board from Mouser or RS

http://www.mouser.co.uk/new/imagination-technologi...

http://uk.rs-online.com/web/p/processor-microcontr...

Step 1: About the CN11 Header

The Creator Ci40 has been designed with a header, CN11, that specifically provides a mechanism for controlling the DC power input from CN16.

(Note CN11 does not control the USB power path. If you are powering your Ci40 via USB a separate control mechanism is required.)

CN11 allows easy access to the enable line of the input DC/DC buck convertor (PSU).

The control states of CN11 are shown in the table below.

Power | Connection

On | Open circuit

Off | Connected together

Step 2: Using a Passive Rocker Switch

The figure shows a simple ON/OFF switch attached to the Creator Ci40 board. CN11 is cabled to a remotely mounted rocker switch using a custom two wire cable. Since the switch is only controlling the PSU enable signal, the current is only a few mA. This means that many types of switch can be used to control the PSU enable.

Step 3: ​Using an Active Switch

It is also possible to remotely control the Ci40 power from an active source, such as another processor board, timer or PC, using the same CN11 header.

If using an active switch then control signal driving into CN11 need to be isolated for correct operation and to prevent possible damage. (The enable line must not be directly driven from 3v3 logic.)

Example interface circuits are in the figure.

Step 4: Find Out More

If you'd like to find out more about the Creator Ci40 IoT hub check out

www.creatordev.io

And technical documentation about the board can be found at

docs.creatordev.io