Shocktty diodes: working principles and appllications

Shocktty diodes are types of diodes that allows current to flow in one direction. Shocktty diodes have low voltage drop of about 0.2 whereas p-n junction diodes have a voltage drop of 0.7 in the forward bias. The voltage drop across the diode is use to turn it on. Normal diodes are made from the junction of an N-TYPE semiconductor and P-TYPE semiconductor, but shocktty diode is made from the junction of a metal and an N-TYPE semiconductor. Unlike other diodes, in Shocktty diode the P-TYPE semiconductor is replaced with metals like aluminium and platinum. The diode is named after a German physicist, Walter H. Shocktty.

The white strip on one side of the diode indicates the cathode while the other indicates the anode.

Circuit symbol of shocktty diodes.

   

Working principles of shocktty diode.

A shocktty diode is made from junction of metal to an N-TYPE semiconductor. Between the junction exists a barrier known as the depletion layer. When current is applied to the diode in forward bias with a negative voltage applied to the N-type and a positive voltage applied to the P-TYPE, current flows without any obstruction. In the forward bias mode, current flows from the metal to the N-type semiconductor then to the source.

For the shocktty diode to conduct electricity in the forward bias mode, electrons in the N-type semiconductor have to overcome the barrier between the junction. So little voltage of about 0.2v is use to overcome this potential barrier. It is more advantageous than other diodes because has low noise and fast recovery unlike other types.

Operating modes of shocktty diodes.

•Forward bias.

All diodes as well as shocktty conducts only in forward bias except zener diodes. For shocktty diode to conduct in the forward bias,   the negative terminal of a power source is connected to the metal contact while the positive terminal is connected to the positive terminal of the power source. 

•Reverse bias.

When a positive voltage is applied to the N-TYPE of  the diode and a negative voltage is applied to the anode it blocks current from flowing because of the N-type semiconductor can't conduct positive charge, but the metal can allow negative charges to flow. the depletion layer widens and current is blocked from passing through the junction with infinite resistance. 

Circuit appllications of shocktty diodes.

•Rectification.

 Shocktty diode are use for rectifying current i.e AC or flunctuating DC. AC can be rectified into DC by means of one or more shocktty diodes connected together either to rectify hafly or fully. 

• Short circuit protection. 

It is use for protecting short-circuit and backward EMF in electric motors.