DIY Arduino Wire and Relay Shield

 

Introduction

Prototyping Arduino sketch in physical hardware requires only an Arduino board, breadboard, its related components, and its accessories. Hardware prototyping on breadboard doesn’t require any lead soldering, but it may have a risk in components burning, etc.

DIY Arduino Wire and Relay Shield

 

An Arduino shield is a ready-to-use electronics module that plug into an Arduino Single Board Computer (SBC) – for example a motor driver module, an Ethernet module. The are a vast majorities of Arduino module available at low cost.

DIY Shield for Arduino Uno

I have a few Arduino Uno SBC. Some discrete electronic components available in my own warehouse. I usually annoying with errors while circuit prototyping on breadboard. With a new version of PCB design, a template of Arduino shield designs were available.

Schematic Design

I putted two main categories of module on a single Arduino shield design – Wire and electro-mechanical relay.

Wire typically called Two-wire Serial Communication (TWI) devices. On this shield it contains a DS1307 Real Time Clock (RTC) and a serial EEPROM.

An SPDT electro-mechanical relay is additionally added on this shield due to the present of free space on its PCB.

D1 is an optional indicating LED to check the output frequency of square wave output from RTC.

There are two input output connectors for relay. It can be used for both DC and AC voltage.

Circuit Design

Proteus project wizard contains a design template for Arduino shield. We will select a template for Arduino Uno shield for ease of design.

A view of circuit design in EDA software

However I additionally draw the schematic in schematic design section before making the PCB design because the template is only presented as the skeleton of PCB.

Circuit Pattern

As it’s shown in the picture above, it seems to be a double sided PCB with a few top copper layer tracks. We can ignore the top copper track, and fabricate this design by hand with only the bottom copper layer. Toner-transfer-method is a first priority for most hobbyists and students.

Bottom copper layer for soldering

Top layer contain both top copper tracks and components legend.

Top layer for components placement

Completed DIY PCB

I made this prototype by hand using a simple toner-transfer-method.

Top layer components placement

Bottom copper was fine due to a good circuit protection during lamination to transfer toner to the copper sheet.

Bottom copper soldering layer

 Some long male header pins for Arduino shield is required for this DIY circuit board. Click here to download zip file of this design. Proteus version must be 8.9 or higher.