What is Gallium Nitride (GaN charger)?

General speaking, Gallium Nitride (GaN charger) is a charger, which has physically smaller, higher efficiency and running cooler than current.

Thinking back to the scene of the electronics class when you entered college, where professors taught you how circuits work with transistors, whose switches are controlled by other electronic components. Now that we've left college campuses and been designing circuits for many years, we know this is not a very nice transistor model. Transistors are affected by series impedance, which is RDSON, and they are also affected by shunt capacitance, which is COSS. Most power supply designs, topologies, architectures, and almost all problems you encounter in power engineering. It will involve how to get rid of the limitations of these two parameters. The losses caused by these and components are 1/2*CV² for COSS because it is a capacitor that discharges through RDSON when the switch is turned on, in addition, the losses are also affected by the frequency component F, which can be Written as 1/2*CV²*F, this is the loss associated with capacitance. RDSON is only valid when the switch is on, where the loss is I²*R. If we can minimize the effects of COSS and RDSON, then we are closer to an ideal transistor. Gallium nitride does this for us, enabling us to make power supplies that are more efficient, run cooler, and smaller in size. Let me tell you how it does it.

Using GaN to build more efficient power supplies. For example, here is a coordinate system, which is a bit like building an Access curve chart, and I will use the X-axis to represent the size of the physical size of the power switch, and the Y-axis to represent the power loss size Loss, look at the RDSON and COSS of standard MOSFETs, you will It was found that the losses decrease as the size of the MOSFET increases when the losses associated with RDSON are taken into account, here is the losses of RDSON. As the transistor size gets larger, the losses also decrease. However, as a transistor gets larger, its output capacitance also increases, and the end result is capacitance-induced losses that increase with transistor size. Capacitor-related losses C and resistor-related losses R intersect at a point, and the best switch utilization is here, where two lines meets, and you get the smallest combined resistor-capacitor losses. Of course, the losses are also affected by the frequency F, which is what switching frequency you choose to operate.
As shown in the curve, let us imagine that it is used to represent the switching characteristics of standard MOSFETs, and gallium nitride is a very special material. Its RDSON, we say the RDSON specified by the specification, is related to the physical size of the device. RDSON is very low, so we can see that as the physical size increases, RDSON decreases more, and another wonderful thing is that her capacitance value is also very low, increasing from a position close to the origin, But this ramping curve is much flatter, so GaN losses are minimal at the intersections, and you can take advantage of that to its switching advantages, because GaN can do some of the things you want it to do, which you wouldn't be able to do with conventional MOSFETs at all. Can't do it. Considering the losses of COSS and RDSON, the benefit of reducing the total loss is to improve the efficiency and reduce the heat dissipation. According to this curve, we can also see another benefit. As a reminder, there is this in the CV²*F. For the component of F, the losses are frequency dependent, which means that if you want, you can increase the switching frequency of the GaN switch and the losses will be slightly higher than at the crossover point, but not to the same high loss levels as MOSFETs. So that, you can increase the switching frequency, of course, not always fully in real life because the switching frequency is also limited to some extent by the magnetics and other parasitic elements in the circuit, but at least you don't will again be limited by the power switching speed.

Next, let's talk about the efficiency improvement brought by the use of gallium nitride, and then draw a coordinate system, the horizontal axis represents the load of the power supply, 100% load, the vertical axis is used to represent the efficiency of the corresponding power supply, It's 100% at the top, but let's start with 80%, because that's a common efficiency baseline for the key sources we're talking about, a power supply based on a MOSFET design, which typically has a light load efficiency of 80%+, let's take a 65W adapter in reverse. Taking the Flyback design as an example, we will see that its efficiency finally approaches the 90% level, which we call 90% full load efficiency. Based on gallium nitride power supply, especially the power supply that integrates the power switch inside the chip, its switching mode has been specially adjusted, and the efficiency will be relatively high under light load conditions, but will also be relatively high under full load conditions, and the efficiency is as high as 93%. That's a 3% increase in efficiency just because of the gallium nitride, which doesn't seem like much of a small number now, but when you compare it to where we are on the curve, you'll notice that it's 3% of 10%, and 10% represents the loss of the power supply, so you save 30% of the loss that would have been in the power supply, so you can save 30% of the energy, which is the original consumption in the power supply. Dissipated energy reduced by 30%. 10% represents the loss of the power supply, the power supply is smaller in size, has a longer life, and the power supply itself does not get hot, so there are many benefits. Energy efficiency regulations from regulators are getting stricter these days, and often you can meet them with a MOSFET-based power supply. But with gallium nitride-based power supplies, you can make smaller, more compact, lighter and more portable products that can be more efficient, even for the same size. No matter how you think about it, there will be social benefits.

For more inquiries, please follow Shenzhen SOY technology co., ltd. or contact sales@szsoy.com.