## Introduction: Make PCB Pattern of LEDs Arranged in a Circle

Make PCB pattern of 12 LEDs arranged in a circle.

Use LibreOffice calc and KiCad.

## Step 1:

Coordinates (x, y) of LEDs and resisters position are obtained by

x = r sin( s ) + a

y = r cos( s ) + b

where x, y are the coordinates of the points on the circle,

r is the radius of the circle,

s is the angle

and a, b are the coordinates of the center of the circle.

.

## Step 2:

On LibreOffice calc, they are

=$B$16*SIN(RADIANS(B3))+100

=$B$16*COS(RADIANS(B3))-100

in the cells.

### Attachments

## Step 3:

The positions of LEDs, Resisters(Pattern1) and Resisters(Pattern2) are shown in the graph draw by calc.

## Step 4:

Set obtained coordinates in KiCad.

## Step 5:

Set rotation value in KiCad.

## Step 6:

Then you can get LEDs and resisters PCB pattern.