Protoboard (Breadboard) Guide Version April 2011 Dept. of Electrical & Computer Engineering Portland State University Copyright © 2008-2011 Portland State University Protoboard Guide ECE – Portland State University a b c d e f g h i j + – 1 1 5 5 10 10 15 15 20 20 + – Figure 2: Internal protoboard wiring • The left and right halves of the protoboard are independent (no internal connection). • The vertical rail lines along the sides are independent from the grid in the center. • Within the grid, each row is independent from any other row. • The five holes of each half-row are wired together. • Warning: Excessively large voltages or currents can damage the protoboard! Figure 1: Typical protoboard unit 1 Protoboard Guide ECE – Portland State University EXAMPLE: The cathode (negative) lead is on the flat side of the LED housing. R V + – + Flat side LED - Cathode Anode Schematic LED Leads The round component is the LED. +V The color banded component is the resistor. – The wire leads of the LED and resistor are inserted into the holes of the protoboard. + Ground The bright red lines are insulated connection wires. Sample Circuit Connection +V + – Ground Alternative Connection 2 There are many ways to connect a circuit on a protoboard. Usually, a simple and neat setup is preferred for easier tracing and debugging.