soldering.md

Assembly

Before starting assembly

• Check the components are complete. See BOM.
• If you are not used to soldering, learn how to solder components.
  • https://learn.adafruit.com/adafruit-guide-excellent-soldering/tools

Soldering

Zener diodes (D49,50)

Solder D49 and D50.
Diode is a polarized component and therefore take care of direction.
A Black line on diode is cathode. (square pad on pcb)

Resistors (R1,2,3,4,7,8)

Solder resistors. Don't place on R5 and R6. (They are for i2c)

Ref	Value	Color code
R1,7,8	1.5k	Brown/Green/Red/Gold
R2,3	75	Purple/Green/Black/Gold
R4	10k	Brown/Black/Orange/Gold
R5,6	I2C	Do not place

Diodes 1N4148 (D1-48)

Diode is a polarized component and therefore take care of direction. A Black line on diode is cathode. (square pad on pcb)

Crystal

Capacitors (C1,2,4,5)

There are 2 kinds of lead pitch.

Ref	Value	Lead pitch
C1,2	22pF	2.5mm
C4,5	0.1uF	5mm

USB connector

Narrow pitch! Be careful of solder bridge between pins.

LEDs

LED is a polarized component and therefore take care of direction. A short leg is cathode. (square pad on pcb)

If you use leds, make bridge J4 and J5 on bottom side.

IC socket

Solder IC socket. IC socket is a polarized component and therefore take care of direction. Check the notch on silk and IC Socket.

Electrolytic capacitor(C3) and Resettable fuse(F1)

Electrolytic capacitor is a polarized component and therefore take care of direction. A short leg is cathode. (square pad on pcb)

And after soldering resettable fuse, bend like the image.

Tactile Switch(SW50,51) and pin header

ATMEGA328p

Insert ATMEGA328P into IC Socket.

ATMEGA328 is a polarized component and therefore take care of direction. See the image.

Check list before connect USB

• No short between VCC and GND, USB connector pins.
• Direction of polarized components.(ATMEGA328p, diode, resettable fuse, electrolytic capacitor)
• Resistor value

NEXT

Connect USB cable and test bootloader