Zener 3.3 V

Description
These 3.3V Zener diodes are well suited for protection on 3.3V circuits like those found on the Raspberry Pi. A Zener diode works like a conventional diode up until the point you hit the breakdown voltage (the point at which the diode can no longer “hold back” the current trying to flow backwards in your circuit). A “normal” diode will allow current flow to reverse direction when the breakdown voltage is exceeded while a Zener diode allows everything over the breakdown voltage to trickle through while holding back the rated voltage. Zener diodes make great low current voltage stabilizers, reference voltages, and are one method of protecting I/O pins from over-voltage.
These specific diodes are rated at 1W and 3.3V.
Features
Power Dissipation: 1 Watt
Forward Voltage: 0.68V
Zener Voltage: 3.3V
Voltage Tolerance: 5%