There are many transistor options on the market today that combine various technologies with different semiconductor materials. As a result, it can be confusing to narrow down which one is the most suitable for a particular design. Among these choices are GaN transistors, but what makes them stand apart from the others?
What are Transistors?
Transistors perform two main tasks in an electronic circuit: they either amplify input current or they essentially act as switches — and both are functions critical to modern electronics. Transistors can be found in digital electronics applications; including radar, air traffic control systems, space exploration, and telecommunications.
Transistors fall into two basic categories based on how they operate: BJTs (Bipolar Junction Transistors) or FETs (Field Effect Transistors). Of particular interest are HEMTs (High-Electron Mobility Transistors), which are often used in high power amplifiers for RF applications.
GaN Transistors Basics
The semiconductor material used for transistors has traditionally been Si (Silicon), but there are more options available to engineers. These include SiC (Silicon carbide), GaAs (Gallium arsenide), and GaN (Gallium nitride). Of these choices, GaN is rapidly becoming the preferred semiconductor material for many transistor applications.
GaN has high electron mobility, supporting more gain at higher frequencies, and does so with better efficiency compared to the equivalent LDMOS (Laterally Diffused MOSFET) technology. GaN also has a high activation energy, which results in excellent thermal properties and a significantly higher breakdown voltage.
The Benefits of GaN Transistors
GaN on SiC transistors offer numerous benefits over the more traditional technologies mentioned above. These include a higher power density, higher breakdown voltage, higher thermal conductivity, and reduced power requirements. These benefits can lead to better efficiency (even at higher frequencies), a smaller form factor, lower overall system class, increased reliability, and best-in-class performance. The use of GaN transistors supports key RF demands such as high gain, low power consumption, high throughput, and extremely fast switching speeds.
For example, when GaN transistor technology is used in amplifiers for telecommunications, it supports a much wider signal bandwidth. Amplifiers that use GaN HEMTs can take advantage of higher frequencies and, as a result, process traffic more efficiently than their more traditional silicon-based counterparts. Fewer amplifiers are required, which results in lower operating and deployment costs because less equipment is needed. In addition, GaN transistors make it possible for numerous systems such as air traffic control to span L, S, C, X, and Ku frequency bands.
GaN transistors can handle a wider range of temperatures than their traditional counterparts and work well in rugged environments, making them an ideal choice for RF applications. For mission-critical RF applications where failure is not an option, GaN on SiC transistors are recommended because of their high reliability.
Where GaN Transistors are Used
GaN transistors are making a significant impact in the communications industry because of their fast switching capabilities and their small, lightweight, durable design. GaN on SiC HEMTs can be found in TCAS (Tactical Collision Avoidance System), radar and broadband systems, UHF communications, inflight WiFi, air traffic control, and IFF (Identification Friend or Foe) systems on military aircraft. GaN RF transistors are used in SSR (Secondary Surveillance Radar) and satellite communications, as well as both broadband and ultra-broadband applications. GaN on SiC components are also used in recent 4G applications, as well as cutting-edge 5G technology. In fact, 5G systems are one area where GaN on SiC transistors are proving indispensable because of the low latency and high switching speeds.
GaN Transistors: Proven Reliability and Efficiency
GaN transistors have been proven reliable, efficient, and effective — a modern transistor for cutting-edge developments such as 5G telecommunications, beyond line-of-sight communications, and satellite technology. When selecting RF components for a design that requires a small form factor, minimal cooling requirements, fast switching speeds, and high-power density, remember to include GaN technology among the choices.