Backward diode

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The schematic symbol for the backward diode, annotated to show which side is P type and which is N; current flows most easily from N to P, backward relative to the arrow.
The schematic symbol for the backward diode,[1] annotated to show which side is P type and which is N; current flows most easily from N to P, backward relative to the arrow.

In semiconductor devices, a backward diode is a variation on a zener diode or tunnel diode having a better conduction for small reverse biases (for example –0.1 to –0.6 V) than for forward bias voltages.

The reverse current in such a diode is by tunneling, also known as the zener effect.[2][3][4]

Contents

[edit] Current–voltage characteristics of backward diode

The forward I–V characteristic is the same as that of an ordinary P–N diode. The breakdown starts when reverse voltage is applied. In the case of zener breakdown, it starts at a particular voltage. In this diode the voltage remains relatively constant (independent of current) when it is connected in reverse bias.

[edit] Applications of backward diodes

[edit] Detector

Since it has low capacitance and no charge storage effect[3], and a strongly nonlinear small-signal characteristic, the backward diode can be used as a detector up to 40GHz.

[edit] Rectifier

A backward diode can be used for rectifying weak signals with peak amplitudes of 0.1 to 0.7 V.

[edit] Switch

Backward diode can be used in high speed switching applications.

[edit] References

  1. ^ Stanley William Amos, Roger S. Amos (1999). Newnes Dictionary of Electronics. Newnes. ISBN 0750643315. 
  2. ^ Anwar A. Khan and Kanchan K. Dey (2006). A First Course in Electronics. Prentice Hall of India. ISBN 8120327764. 
  3. ^ a b S.L. Kakani (2004). Electronics Theory and Applications. New Age Intl. Ltd. ISBN 8122415369. 
  4. ^ Karlheinz Seeger (2004). Semiconductor Physics: An Introduction. Springer. ISBN 3540219579.