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Identifying the Components

Printed Circuit Board​

The printed circuit board is responsible for holding all the components. It can be made of fiberglass or phenolic. For the Franzininho DIY, a single-sided design was developed, which allows home manufacturing.

PCB

On the top side of the board (TOP) there are component outlines indicating the position of each one. The components are inserted in their respective locations and then soldered through the bottom side (Bottom).

TOP and Bottom of the Franzininho DIY V2 Board

Resistors​

Resistors are passive components that oppose the flow of electric current in the circuit. There are several types of resistors available. In the Franzininho DIY we use 1/4 W carbon resistors. The color bands indicate the resistance value and tolerance.

Color Code Table for 4-band Resistors

Source: http://blog.render.com.br/eletronica/como-calcular-o-valor-de-um-resistor/

In the Franzininho DIY we use 5 resistors, with the following references and values:

  • R1 and R2 - 68 R (Blue, Gray, Black, Gold)

68 Ohm Resistors

  • R3 - 1K5 (Brown, Green, Red, Gold)

1500 Ohm Resistor

R4 and R5 - 1K (Brown, Black, Red, Gold)

1k Ohm Resistor

Capacitors​

Capacitors are electrical devices capable of storing electric charge in an electric field. In the Franzininho DIY we have 2 types of capacitors:

C1 - Ceramic Capacitor 100 nF x 50 V

Ceramic Capacitor 100 nF

C2 - Electrolytic Capacitor 10uF x 35V

Electrolytic Capacitor 10uF x 35V

LEDs​

The LED (Light Emitting Diode) is used for light emission in places and instruments where it is more convenient to use instead of a lamp.

In the Franzininho DIY two 3 mm diffused LEDs are used:

ON - Green LED, LED - Yellow LED

3mm LEDs

Tactile Switch​

It is a momentary contact button. In the Franzininho DIY we use a normally open (NO) tactile switch of 4.3 x 6 x 6 mm that serves as the Reset button.

Switch - RESET

Tactile Switch

Socket​

The socket is used to mount integrated circuits, making it easy to replace them on the board.

In the Franzininho DIY we use an 8-pin socket to accommodate the ATtiny85 microcontroller.

IC1 - Socket

8-pin machined socket

Pin Headers​

Pin headers are used for pin expansion and power input on the board. In the Franzininho DIY we use 3 pins for the power connector and 8 pins for the board expansion connector.

  • J1 - 3-pin header
  • P0, P1...GND - 8-pin header

Pin Headers

Voltage Regulator​

Used to step down the input voltage to a level at which the circuit can operate. In the Franzininho DIY we use a 5V voltage regulator, the 78L05.

IC2 - 78L05 - 5V Voltage Regulator

78L05 Voltage Regulator

USB Connector​

Used to connect the board to a computer or a power supply circuit with a USB connector. In the Franzininho DIY we use a 90° Male USB Connector with latch.

90° Male USB Connector with latch

ATtiny85​

This is the brain of the Franzininho DIY and the most expensive component. Be careful when inserting it into the socket. Follow the assembly guidelines.

ATtiny85