First Foray into KiCad

KiCad is a free software tool for designing Printed Circuit Boards, and can generate files to use with services like PCBWay. PCB manufacturing is getting so cheap now that it is hard to justify all the time and bother of old-fashioned soldering in a project with more than a dozen traces.

KiCad is a bit intimidating at first because of the many pages of the manual and tutorials, and a large forest of minor details. But I think it is not so scary once you understand the basic workflow:

1 – Put together a schematic. This shows the basic types of components (“symbols”) in your circuit and how they interconnect.

Somewhat embarrassing first schematic using KiCad.

2 – Assign “footprints” to your symbols. Footprints basically are the actual hardware you want to match to the component type.

3 – Use the new PCB tool to generate a PCB based on your schematic. You need (in a simple design) to lay out the traces and ground plane on your front and back copper layers, and then lay out the shape of your board in the edge cut layer.

Simple PCB design in KiCad

You can then view the PCB in 3D view if you wish.

Simple PCB design in 3D View

One hundred dollars in Monopoly money to the first person who can figure out what that circuit does!

And finally you generate Gerber files, which can be submitted to a service like PCBWay. You pay for the service, and they send the board with traces, holes, pads, labeling, and artwork as specified. You get the components separately and solder those on yourself.

XL6009 Voltage Boost Converters

XL6009 Boost Converter in NPN Transistor Switch

The large module is the the XL6009 Boost Converter, which is boosting a 5 V source to 21 V. There is a small screw on it that you can turn to select other voltages (i think it goes up to 35 V).

It is tied into an NPN transistor, set up for switching. The base of the switch is driven by a 5 V signal from the Uno, with a 10k resistor, which turns on the collector-emitter path, which being driven by the 21 V source, with a 1k resistor, and providing current for the LED.

I needed a 21 V source for my EPROM programming project, but needed it to be controlled by a 5 V AVR pin.

A pack of XL6009 Boost Converters is available for about $12 from Amazon.