2. Diodes

Step 1: Breadboard the circuit

Step 2: Open Falstad simulation

Step 3: Questions

Falstad Circuit Simulator: Diodes


Diodes only allow current to flow in one direction, like a one-way valve. (LED = Light Emitting Diode)

Like resistors, diodes will also have a voltage drop. Our diodes have a 0.6V – 0.8V drop, and LEDs are between 1.7V – 3.2V depending on their colour.

Unlike resistors, diodes always have the same voltage drop. Resistors’ voltage drops increase with more current.


Theory 2

1. What is the voltage drop across the LED on Falstad? (Look for Vd)

2. What happens if you install the diode backwards on your breadboard?

3. The voltage drop tells us that the diode is consuming power, but where does this power go?

4. What is the difference between an LED and a diode?