# Electronic Design

## Assignment : Redraw the Echo-Hello-World Board

I don't understand about electricity very well.
So I studied and filled out some words about electricity.
Then I made some circuit using a breadboard for understanding electric behavior.

Glossary
• Capacitor : Capacitor is a passive two-terminal electrical component used to store energy in an electric field.
• Resonator : Resonator is a device that exhibits resonance, that is,
It naturally oscillates at some frequencies, called its resonant frequencies, with greater amplitude than at others.
• Inductor : Inductor is a passive two-terminal electrical component that stores energy in its magnetic field.
• Inductor : Inductors are one of the basic components used in electronics where current and voltage change with time, due to the ability of inductors to delay and reshape alternating currents.
• Vcc : Vcc is place where supply voltage to circuit. Vcc is written when Bipolar is used, vdd is written when unipolar is used.
• GND : GND is standard electric potential. Voltage of some parts are calculated compared with GND.
• SMD : SMD is Surface Mount Device.

### I made circuit using a breadboard.

At the beginning I connected a LED and power supply directly, therefore broke some LED.
I learned that I need to put some resistor between LED and the Power Supply.

### Then I made a circuit which had cds sensor.

This circuit become luminous when get dark around the sensor. From this thing, I understood resistor's behavior.

#### I also made this circuit which is named multivibrator.

As I made this circuit, I understood capacitor and transistor's behavior.

### Design circuit using EAGLE

After I understood electric behavior, I studied how to draw circuit using EAGLE.

-What I study-
When I use LED, I have to connect resistor.
And I can adjust brightness of LED change resistor.

#### Export png file and edit

I redrew png file using GIMP. I filled picture, then made the outer frame.

### Milling

I was sending png data from computer to Modela using the Fab Module.

### Soldering

Parts
• 6 pin Header(1)
• Single Row 2.54smd(1)
• 20Mhz Resonator(1)
• Resistor 10KOhm(1), 1KOhm(1)
• Capacitor 1uF(1)
• ATiny44A(1)
• LED(1)

#### Put the glue using the Gluegun.

Because Header pin is unstable.

### Check a LED

At the beginning when I checked a LED, LED was not working.
Because LED was broken.
So I changed LED, LED worked.