Shockley diode

It is a PNPN diode with alternating layers of P-type and N-type material.

The construction includes four sections of semiconductors placed alternately between the anode and cathode in the pattern of PNPN.

When the voltage exceeds the trigger value, the resistance drops to an extremely low value and the device switches ON.

On reducing the voltage to a sufficiently low level, the current flowing becomes insufficient to maintain the transistor bias.

Common applications: Niche applications: Small-signal Shockley diodes are no longer manufactured, but the unidirectional thyristor breakover diode, also known as the dynistor, is a functionally equivalent power device.

A sculpture representing a Shockley 4-layer diode , on the sidewalk in front of the new building at 391 San Antonio Rd., Mountain View, California , which was the original site of the Shockley Semiconductor Laboratories where the first silicon device work in Silicon Valley was done
V–I diagram
Dynistor