Advantages of TRAPATT diode | disadvantages of TRAPATT diode
This page covers advantages and disadvantages of TRAPATT diode. It mentions TRAPATT diode advantages or benefits and TRAPATT diode disadvantages or drawbacks.
What is TRAPATT diode?
The diode is microwave energy source used as both amplifier and oscillator. It is the short form of TRApped Plasma Avalanche Triggered Transit diode. It works efficiently below frequencies of 10 GHz. It requires greater voltage swing for its operation.
The figure-1 depicts TRAPATT diode structure. It consists of p+ - n - n+ (or n+ - p - p+ ) structure with n-type depletion region with width range from 2.5 to 12.5 µm. The diode diameter has dimension from 50 to 750 µm. They are usually manufactured using silicon. The p+ region is kept very thin which ranges from 2.5 to 7.5 µm.
The figure-2 depicts TRAPATT diode waveforms describing its operation at different points. Refer difference between BARITT vs IMPATT vs TRAPATT diodes>>.
TRAPATT diode is used for following applications.
• Microwave beacons
• Local oscillators in Radar
• ILS (Instrument Landing System)
• S-Band pulsed transmitters for phased array radar
• Radio altimeter
Benefits or advantages of TRAPATT diode
Following are the benefits or advantages of TRAPATT diode:
➨It offers higher efficiency compare to IMPATT diode. Efficiency of about 15 to 40 % can be achieved.
➨It has very low power dissipation.
➨It is most suitable for pulsed operation.
➨It can operate from 3 to 50 GHz.
Drawbacks or disadvantages of TRAPATT diode
Following are the disadvantages of TRAPATT diode:
➨It is not used for continuous operation mode as it offers high power densities i.e. 10 to 102 W/m2.
➨It has very high noise figure which is about 60 dB.
➨It supports frequencies below millimeter band.