Diodes

One-way streets for current

An interactive lesson with 7 steps, about 6 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• A p–n junction forms a depletion zone with a built-in field.
• Forward bias above about 0.6 V conducts. Reverse bias blocks.
• Diodes rectify AC into one-way current.

Steps

1. The p–n junction
2. Building the barrier
3. The diode curve
4. Ten times per 60 millivolts
5. Double the current
6. Current through a diode
7. Charging from the mains