When is the last term you got excited about chargers. I know, you don’t have an answer. Well, then you should get excited about GaN chargers.
Why does it matter? What if your charger can become much smaller, much faster in charging and universal as well (one charger for multiple devices).
Sounds cool right? With chargers now being inseparable parts of our life. The thought of our chargers becoming more compact and fast and universal for all our devices seems something to get excited about.
Introducing GaN chargers. Lets dive into all about GaN chargers
GaN charger is a charger which uses GaN based semiconductor components instead of silicon (Si) to charge your electrical devices.
GaN stands for Gallium Nitrate.
Generally, Silicon is the preferred material for making transistors which is used in charger. But the GaN charger uses Transistors based on GaN. Thus called GaN chargers.
Both GaN and silicon along with some other materials like Boron, Germanium are part of a special group of material known as semiconductors. Before understanding difference between GaN based chargers and silicon chargers. We need to know what are semiconductors.
What are semiconductors, How they are related to electronics?
Semiconductors are material who are neither completely conductors nor insulators. Their conductivity can be altered by introducing impurities in them (this process is called doping). Thus, they are called Semi-conductors as they conduct semi, not fully.
Semiconductors have properties such as
They can pass current more easily in one direction than the other,
they can have variable resistance,
sensitivity to light or heat.
These properties are what makes semiconductors like Silicon(Si) and Gallium Nitrate(GaN) perfect for use in electronics.
Some terminologies related to Semiconductors
Semiconductors are defined by their unique behavior of electric conductivity. They are somewhere in between insulators and conductors.
Now, these insulators, semiconductors and conductors vary from each other in terms of band gap.
You already know, everything is made up of atoms. Atoms have neutrons, protons and electrons inside them. With, Electrons orbit or revolve around the nucleus of the atom.
The orbits or curved path of electrons are grouped into energy levels called shells and the outermost shell is called Valence shell. Since this Valence shell represents different bands of energy levels. Therefore, also known as Valence band.
What is Valence Shell or Valence Band?
The electrons in this valence band are called valence electrons.
These electrons when gain enough energy from external source can escape from valence band and move to conduction band.
Now conduction band is a band of energy levels located in the atom where electrons are free to move thus it is called conduction band
Now electrons move from valence band to conduction band.
The amount of energy required by an electron to move from valence band to conduction band is called band gap
The band gap is measured in eV. The band gap vary in insulators , conductors and semiconductors.
If the band gap is big, electrons will have a hard time jumping to the conduction band, which is the reason of the material’s poor conductivity.
High Band gap
Small band gap compared to insulators
No band gap, valence and conduction band overlap
What is GaN ?
GaN stands for Gallium Nitride. It is a type of semiconductor, just like Silicon.
Gallium Nitride is a human synthesized material, made by combination of Gallium and Nitrogen. It was first synthesized around 1940s.
The first common use of GaN in electronics was in Blue LED’s in the 1990s. Before that, there were no blue LEDs, just red and green LEDs were there.
The team which made blue LEDs also received the Nobel Prize for use of GaN to make Blue LEDs possible.
GaN is also used in making Chargers (as we’re discussing here), Solar panels, radars and finding many applications in various modern electronics.
Now what makes GaN based charger better than our typical Silicon based chargers.
Why is GaN based charger better than Silicon based charger?
In simple terms,
Efficiency – GaN is much more efficient than silicon in conducting current.
High Voltage – can withstand much higher voltages
HighTemperature – withstand higher temperatures, compared to Silicon. GaNs heat limit is 600 °C, while silicon’s is 150 °C.
Size – a typical GaN charger is much smaller than a silicon chip.
Now, we know that a typical charger has an electronic chip inside it. In this chip lie many electrical components.
The heart of this chip is what we call power Transistors. The main difference between Silicon based charger and GaN based charger is due to this transistor only.
The Silicon based charger use silicon (Si) MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) and GaN based charger use GaN HEMTs (High-Electron-Mobility Transistors, also called GaNFET).
Now, the advantages of GaN based charger are due to this GaN HEMTs over Silicon based MOSFETS.
Diving further, the reason for GaN being better is due to the fact that GaN has a wider band gap (3.4 eV) than Silicon, which has a band gap of 1.1 eV. I have already explained above what a band gap is.
The benefits that wider band gap gives are that
It can withstand higher temperature
GaN can operate at higher frequencies
Additionally, GaN has more electron mobility of 2000 cm2/Vs compared to Silicon with 1500 cm2/Vs. Electron mobility is how fast electrons can travel. Thus, GaN has 30% more electron mobility than Silicon.
This higher electron mobility gives GaN the advantage of faster switching speeds. GaN has more switching frequency than Silicon based MOSFETS. Due to this, even the components which are connected to the transistor can be made smaller.
Comparison Between Properties of Silicon and GaN
Advantage it gives
Wider Band gap means , GaN can work in higher voltages and temperatures easily
GaN based products can be used for High voltage and current applications.
Electron move faster GaN . As a result frequency of switching can be much higher.
Due to faster switching, the components used beside GaN transistors can be smaller. Making overall size of chip smaller
Can easily work in High temperatures
The components can be more tightly packed without worrying about the high temperatures it generates. Increasing the overall efficiency as well
A GaN charger will be more efficient, have more power, and will be much smaller than a similarly rated Silicon charger.
All these properties are what makes
Charger based on GaN more efficient than Silicon based charger. GaN based charge has 95% efficiency compared to Silicon with 85%
GaN charger is approximately 40% smaller than Silicon based charger.
Due to more power limit, GaN can simultaneously charge multiple devices. Also, thanks to USB-C, Everything is now USB-C compatible. With USB-C PD reaching 100W. We can simply have universal GaN chargers that can charge our mobile laptops etc. simultaneously.
The technique involves growing a thin layer of GaN on the AIN (Alumium Nitride) layer of a standard silicon wafer. Using metal organic chemical vapor deposition (MOCVD). This new technique of making GaNFETs was first used in 2006.
The reduced defects, use of existing techniques/machinery and packaging have all made GaN transistors much more viable and cost-effective.
Where you can Buy GaN chargers?
As with every new technology trend. A lot of startups and manufacturers are getting on this GaN train. Which is a great thing.
But, some will try to take advantage of this situation as well. They will sell inferior chargers in name of GaN chargers. So, you have to be careful when buying a GaN charger.
Tips for buying GaN chargers
When buying, You should prefer that cable is included with the charger. As, any normal cable will not be able to support the high power charger and your device will ultimately charge slowly only.
The length of the cable should be long enough. Small cables are not that useful.
Also, check out the length of prongs, as short length of prongs will lead to the charger getting disconnected often.
Do check the warranty type and duration. You may not want to spend $50 on a charger without any or useless warranty.
If you’re going with 100W charger. Know about true 100w GaN charger. Keep in mind, not all chargers which advertise 100W are actually 100W. You have to see whether the power from single USB-C port is 100W or not. Some chargers say 100W as some of 2 poets which one port supporting max 65W only and other 35W. They advertise as sum of those two (35 + 65 = 100W)
Check the reviews of the other customers.
There are mostly two variants available in market currently. 65W and 100W.
TECKNET 65W PD 3.0 GaN Charger –
One of the best 65W GaN available. Comes with 1-Year warranty