Inside UGREEN's 500W USB Charger: Nearly Half Its Weight Is Heat-Dissipation Material
イチケン / ICHIKEN
Most USB chargers are rated at 60W or 100W. UGREEN's charger is rated at 500W. In this video, the electronics YouTuber Ichiken measures its specifications, efficiency, and thermal behavior, then takes it apart. The main question is how a sealed, multi-port charger of this size manages its heat. The answer turns out to be a very large amount of thermally conductive potting material, which the reviewer still considers only a partial fix.
A Desk Charger, Not a Travel Charger
The main unit weighs 1,595g. Adding the separate power cable brings the total to 1,854g. Next to a normal USB charger it looks enormous. Ichiken concludes that it isn't meant to be carried around. It is meant to stay permanently on a desk, for example in a conference room. UGREEN previously released a 300W model, and the reviewer places this 500W version above it in the lineup.
Its main selling point is that all ports together can deliver 500W. The top port, C1, can also always output 240W, no matter what the other ports are doing. With a USB PD trigger connected, the charger offered USB PD Extended Power Range (EPR) outputs up to 48V. Ichiken notes that many commercial chargers top out at 140W (28V, 5A), and few offer 36V or 48V. A single port supplying 240W on a multi-port charger makes this, in their words, quite a challenging product.
How Power Is Shared Across Ports
The reviewer summarizes the port allocation from the included manual. Each of the four ports C2 to C5 can supply up to 100W, but the actual limit depends on how many are in use:
- Only two of the four can deliver 100W at the same time.
- With three in use, the split is 100W/100W/60W or 100W/60W/60W.
- With all four in use, each drops to 60W.
Ichiken warns that anyone charging laptops that draw more than 60W should keep this in mind. C1 is unaffected by these limits. The USB-A port at the bottom is limited to 20W, which the reviewer says they rarely use these days.
In normal use it behaves like any other charger, and Ichiken found little to comment on. One practical point they did confirm: plugging a device into an empty port does not interrupt power to devices already connected. That makes it suitable for equipment that needs a constant supply. The reviewer also points out that almost no devices can currently draw 240W, so the headline feature is mostly future-proofing for devices yet to come.
Spec Comparison: Bigger Than Its Power Rating Suggests
Ichiken compares the charger with a typical 45W Anker single-port charger. The UGREEN unit has 11 times the power rating but 28 times the volume, 10 times the surface area, and 27 times the mass. Volume and mass grow faster than power. The reviewer gives several reasons. The Anker is single-port and the UGREEN is multi-port, so the internal circuit architecture differs. The cooling structures differ. The UGREEN also needs more structural components to support its own weight.
Power density confirms this. Recent single-port chargers often exceed 1 W/cm³, but this charger reaches only 0.45 W/cm³. Ichiken attributes this to the circuitry, the cooling structure, and the materials used, and says the teardown would check this.
The second metric is power loss per unit of surface area, based on measured losses. Chargers like this cool mostly by natural air convection over their surface, so a lower number means more thermal headroom. By this metric the charger seems to have plenty of room for heat dissipation. Against the 300W model, the 500W version has lower power density and a lower heat-dissipation index, so on paper it looks designed with more margin.
Conversion Efficiency
Efficiency measures how well the charger turns AC from the wall outlet into DC for USB. Higher efficiency means less power lost inside the charger and less heat. Ichiken first measured the 240W port on its own. Efficiency was high overall and dropped at low power, as with other chargers. Below about 70W output, the internal circuitry ran intermittently, which made measurement difficult.
The results were split into two groups: the 5V–20V range used by ordinary chargers, and the higher voltages. Up to 20V, the peak efficiency was 93.4%. The reviewer notes that for chargers of 100W or less, around 92% is already a good figure. At 28V and above, efficiency rose further, reaching 94.2% at 48V output. Ichiken's explanation is that a power supply rated for 500W runs close to its sweet spot when delivering about half its rating.
Power loss increased fairly linearly and reached about 15W at 240W output. At 20V and maximum output, the loss was comparatively higher. The reviewer guesses that the internal conversion circuit cannot run under its most efficient conditions in that case.
All Ports Loaded: 100V vs. 200V Input
Measuring efficiency with all five ports loaded took an elaborate setup. Ichiken tested with 100V input, as used in Japan, and 200V input, for use abroad. At 200V, efficiency was about 1–2% higher overall, and the gap was clearest above 300W. The power-loss curves showed the difference best: at 500W output, 200V input saved nearly 10W. The reviewer's explanation is that less current flows through the circuit at the higher voltage, and concludes that 200V is the better choice where available.
Thermal Imaging: An Uneven Hot Square
The thermal camera showed a maximum surface temperature of 68°C. Ichiken notes that later experiments found conditions where it got hotter still. The heat pattern was uneven. A square-shaped hot area showed where heat from internal components reached the case, while the corners stayed noticeably cooler. The reviewer's impression was that heat was not spreading well, unlike other USB chargers they have tested, where the distribution is uniform. Ichiken suspected a design issue. They also suspected that the unit's size makes the path from heat source to surface long, so it doesn't cool as well as its large surface area would suggest.
Thermal Throttling in Practice
UGREEN markets a thermal throttling feature, called Thermal Guard. It limits output to keep the charger from damaging itself as it heats up. Ichiken tested it with an initial load totaling 500W: 240W on C1, 60W on each of C2–C5, and 20W on the USB-A port. They recorded the temperature at the hottest point and the total output power over time.
The charger delivered the full 500W from the start, and its temperature climbed as internal losses turned into heat. The throttling then happened in stages:
- After about 70 minutes, at roughly 70°C surface temperature (about what the earlier thermography showed), C2–C5 dropped from 60W to 45W each. Total output fell to 440W.
- About 20 minutes later, C1 dropped from 48V to 36V output. Total output fell to 380W.
- At 180 minutes, the C5 port was cut to 15W. Total output fell to 350W.
After that, the second and third stages kept repeating. Ichiken concludes that 350W is effectively the charger's continuous power rating.
Teardown: Thermal Sheets With Gaps
The charger's core is a module inside an outer shell. Silicone-based thermal sheets line the inside of the shell on all four sides. They were soft, brittle, and easy to peel off. Ichiken found that they did not fill the space between the shell and the internal module tightly, and there were quite a few gaps. Small USB chargers are usually filled solidly with silicone potting, and the reviewer thinks this difference explains the uneven, square-shaped hot spot seen on the thermal camera.
Ichiken also offers a reason for this design. High-conductivity gap filler is surprisingly expensive, and filling that volume with it would be costly. The reviewer assumes UGREEN designed it this way to keep the price down.
An Aluminum Shield and More Potting
The module itself is wrapped in a roughly 1mm-thick sheet of what looks like aluminum. It helps spread heat from the circuit and blocks radiated noise. The 300W model used a brass-like material. Ichiken notes that aluminum conducts heat well and is highly electrically conductive, which is good for electromagnetic shielding. The shield is electrically connected to the circuit board, but aluminum can't be soldered. So it is riveted to a solderable metal, which is then soldered to the board. The reviewer calls this a very robust construction.
Under the shield are resin plates, and beneath those the module is packed with silicone-based thermally conductive potting. Ichiken believes it was poured in from an opening at the top. The potting peeled away in large chunks. There was noticeably more of it on the side that had shown the most heat in the thermography.
Half the Weight Is Heat-Dissipation Material
After removing all the thermal materials, Ichiken weighed them. The potting came to 677g, and adding the four thermal sheets from the shell brought the total to 761g. That is about 47% of the 1,595g main unit.
The reviewer credits UGREEN with a serious effort, but still thinks the structure makes heat hard to get out. In a typical small charger, heat goes from the source through potting directly into the outer casing. In this UGREEN unit, heat has to pass through potting, then plastic, then the aluminum shield, then a thermal sheet, and only then reach the exterior. Each layer adds thermal resistance. The plastic, aluminum, and thermal sheets are not fully bonded to each other, so the gaps add even more resistance. Ichiken describes this as a limitation of a sealed design and a major difference from industrial power supplies.
Circuit Overview and Filtering
The circuit consists of four boards: the main board, the USB board, and plug-in daughterboards carrying power semiconductors. The main board contains the input filter, rectifier, power-factor correction (PFC), and isolated DC/DC conversion. Two wires run through the air to connect secondary-side components such as the Y-capacitor to the primary side. The back of the main board is dense with surface-mount components.
The input filter uses capacitors and inductors and is large. Ichiken explains that a 500W supply tends to leak more noise, so it needs a bigger filter. A white component nearby is a thermostat. Along with other sensors on the board, it gave the reviewer the impression that the whole board is under fairly strict temperature control.
Rectification Without a Bridge Diode
The rectifier turns the filtered AC into DC. This product does not use a bridge diode. Instead it uses an ideal-diode circuit built from a controller and MOSFETs. Ichiken explains that at 500W, conventional diodes would lose too much power. Replacing the diode's forward-voltage drop with the MOSFET's lower on-voltage reduces the loss. On the back of this board, small metal pieces are surface-mounted directly behind the semiconductors. The reviewer thinks they increase the current capacity of the copper traces and help the board absorb and dissipate heat. This area was also fully potted in silicone.
Two Interleaved PFC Stages
The PFC circuit works like a boost converter, and this charger has two of them running alternately under interleaved control. The inductors are, in Ichiken's words, as large as you'd expect for a 500W circuit. Copper was left exposed on the board under them to improve heat transfer, and potting filled those areas to thermally connect the inductors to the board.
The control IC and power semiconductors sit on the back of the main board. The PFC uses GaN HEMTs from Innoscience and SiC Schottky barrier diodes from a manufacturer rendered in the transcript as "Senguoke." Because there are two circuits, the reviewer says UGREEN uses power semiconductors quite generously. There are also what look like ferrite beads for noise suppression. Ichiken wasn't sure what they were and wondered whether they might be amorphous-core parts.
Two Asymmetric Half-Bridge Converters
The isolated DC/DC stage appears to use an asymmetric half-bridge topology, again with two circuits. Each transformer has its own temperature sensor, and these areas are also potted for thermal coupling. The power semiconductors for both circuits sit on the plug-in board: GaN devices from Innoscience again. The reviewer comments that Innoscience is doing well and suspects it is widely used, especially by Chinese power-supply makers. The controller is from Richtek, part of Taiwan's MediaTek group.
The two converters serve different outputs. One is dedicated to C1 and its 240W output. The other is shared by C2–C5 and the USB-A port. Each converter handles exactly half of the total power. In practice, Ichiken says, the shared converter tends to run at a higher load, and the thermography matches this: the area around its transformer was the hottest part of the charger.
The USB Board
The USB board carries inductors and electrolytic capacitors, which Ichiken thinks may be polymer types. All of them serve C2–C5 and the USB-A port. The main board produces 20V, and this board steps it down to whatever voltage USB PD negotiates. Buck-converter MOSFETs on the board support this. On the back is an iSmartWare IC that combines a PD controller and buck-converter controller.
C1's PD controller, also from Richtek, sits on the main board. Because C1 has its own dedicated converter, it needs no voltage conversion on the USB board. The USB board only has a trace to carry C1's CC signal.
Conclusion: A Hard Problem, Handled With Brute Force
Ichiken's summary is that the charger's defining feature is single-port 240W output, and the teardown showed how the circuitry supports it: separate converters, generous use of GaN and SiC parts, and extensive temperature monitoring. The bigger theme is heat dissipation, which the reviewer sees as a central challenge for modern USB chargers. UGREEN's approach is to fill the unit with thermally conductive potting, thermally bond everything, and move the heat out through the casing. Still, Ichiken thinks getting heat out of a high-capacity, sealed switching power supply remains very difficult. With heat-dissipation materials making up about half the charger's mass, and sustained output settling at around 350W rather than 500W, the reviewer concludes that heat was clearly a hard problem for this design.
This video is brought to you courtesy of RAMXEED. Hello. Today we have this monstrous 500W USB charger. I will disassemble and review it. While many chargers in the charger industry are 60W or 100W chargers, UGREEN is truly out of the norm. They've put out a 500W USB charger. We will examine its performance and internal structure. But first, here is today's sponsor.
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First, let's take a look at the exterior. In a word, it's huge. A normal USB charger is this size. Compared with this, I think you can see exactly how big this USB charger is. It weighs 1,595g. The cable is external, and the total weight is 1,854g. Therefore, unlike a small charger, it is not the kind of thing you carry around. I think it is basically intended to stay on a desk, such as in a conference room.
UGREEN previously released a fairly high-power 300W USB charger. I think this 500W version is a higher-end model of that. The best feature of this USB charger is that all ports can be powered with a total of 500W. In addition, the top port is capable of outputting 240W at all times, regardless of the other ports in use.
When you actually plug in the USB PD trigger, you can see that USB PD Extended Power Range, or EPR, output up to 48V is possible. Among commercially available USB chargers, there are many that produce 140W at 28V, 5A. Few can produce higher voltages of 36V or 48V. Given specifications such as a 240W power supply from a single port and being a multi-port charger, I think it's quite a challenging product!
When using multiple ports of this USB charger, the power allocation is written in the instruction manual that comes with it. Briefly, USB-C ports C2 to C5 each have a maximum output of 100W. However, the output power seems to change depending on usage conditions. Only two of these four ports can output 100W at the same time. When using three ports at the same time, the outputs are 100W, 100W, and 60W, or 100W, 60W, and 60W. When using four ports at the same time, the output power drops to 60W for all of them.
Therefore, be careful when charging notebook computers and other devices with power consumption of 60W or more. Only three ports can supply 100W at the same time: C1 and any two of C2 to C5. For the USB-A port at the bottom, the maximum output power is 20W. I don't use it much these days.
As for how it feels to use, it's a common, generic charger. I don't think there's anything in particular to review. Even if you connect to an empty port while it is in use, the power supply to other ports already connected does not stop. I think it is safe to use for items that require a constant power supply.
The most important feature of this charger is its 240W power supply. Currently, there are almost no devices that can receive power at 240W. So I have a strong feeling that this capability is going to waste. For now, we're waiting to see whether compatible devices appear in the future.
Here are the actual specs. We will see what the tables and experiments confirm. Let's start with this specs comparison chart. This is a comparison with a typical 45W USB charger. You'll notice that the numerical values differ by one or two orders of magnitude. It has 11 times the power rating, 28 times the volume, 10 times the surface area, and 27 times the mass. As far as this is concerned, volume and mass appear to increase more than power.
There are several reasons for this. Anker's is a single-port product, whereas UGREEN's is a multi-port product. Therefore, the internal circuit configuration is different. There are also differences in cooling structure and the components used to support the weight of the product itself.
Next we will look at performance indicators. First, power per volume. The larger this number is, the higher the performance as a power supply. Many recent single-port USB chargers exceed 1W/cm³. UGREEN is 0.45W/cm³, so its power per volume is not that high. I think the circuitry, cooling structure, materials used, and other factors I mentioned earlier have an effect. I will actually disassemble it later to confirm.
Next is power loss per surface area. Power losses were measured beforehand. These numbers show how much room the USB charger has for heat dissipation. Since most heat dissipation in such USB chargers occurs through natural air convection, a larger surface area makes the structure easier to cool. For this cooling performance indicator, the smaller the number, the more room there is for heat dissipation. Looking at these numbers, there seems to be plenty of room. I'll experiment and confirm this later as well.
This comparison chart compares it with the lower-end 300W version. Looking only at performance indicators, power per volume is lower, and the heat dissipation indicator is also smaller. Compared to the lower-end model, it looks like a design with plenty of room to spare.
Next, we measured power conversion efficiency. This shows how efficiently AC power from an electrical outlet can be converted into the DC power used in USB charging. The more efficient the USB charger, the smaller the power loss generated by the charger itself. This results in less heat.
First, here are the measurement results for the 240W single port. The horizontal axis is output power, and the vertical axis is conversion efficiency. Overall, efficiency is quite high. At low power, efficiency is lower, as with other chargers. Incidentally, below 70W output, efficiency measurement was difficult because the charger's internal circuitry operated intermittently.
This graph is a little hard to see, so we will separate the graphs for 5V to 20V, which are available on common chargers, from those for higher voltages. First, here is the case up to 20V. The highest efficiency was 93.4%. That's quite efficient for a USB charger. For USB chargers of 100W or less, a conversion efficiency of around 92% is pretty good.
Next, here's the range of 28V and above. Efficiency is even higher: 94.2% at 48V output. It's quite efficient. The reason is that we're using a power supply rated at 500W at about half its rating, in just the right operating range.
Here is the power loss curve. It increases fairly linearly. At 240W output, there was a power loss of about 15W. These results show that at 20V and maximum output, there seems to be more power loss. I think these are conditions where the internal conversion circuitry cannot operate efficiently.
Next are the efficiency results when all ports are used. I'm using an experimental setup like this. It was hard to measure because there were five ports. Measurements were taken at two input voltages: 100V for use in Japan and 200V for use overseas. The 200V input is more efficient, with overall efficiency about 1–2% higher. The difference is particularly visible in the high-load range of 300W or more.
The power loss curve makes this even clearer. At 500W output, for example, the difference is nearly 10W. Basically, at 200V, less current flows in the circuit. I think that may be having an effect.
Next, the temperature of the main unit was measured using a thermal imaging camera. The maximum temperature was 68°C. It's getting hot. There is one caveat, though: as the experiment continued, there were conditions where temperatures were higher than this. I'll explain that later.
If you look closely, you can see a square shape where heat from the internal parts is transmitted to the surface. As for heat distribution, only certain areas are warmer, and temperatures are lower in the corners of the enclosure. There is a temperature difference overall. I have the impression that the heat is not diffused well. Other USB chargers have a uniform temperature distribution. It must be a design issue. I'll disassemble it later to check.
The other thing is the size of the main unit. The heat transfer path from the heat source to the surface is long. It's not as cool as I thought it would be. I think it is difficult to cool.
Next, in relation to temperature, I also checked whether thermal throttling occurs. Thermal throttling is a function that intentionally limits output power to prevent the USB charger from breaking due to heat. UGREEN calls this feature Thermal Guard™. As I hinted earlier, this charger has thermal throttling.
Here are the results of the experiment. The graph is a little hard to see. The horizontal axis is the time elapsed since the start of the experiment. The left vertical axis is the USB charger's temperature, measured at the hottest part. The right vertical axis is the USB charger's output power. The initial output powers, from top to bottom, are 240W, 60W, 60W, 60W, 60W, and 20W, for a total of 500W.
The results show that it outputs 500W right from the start. The resulting power loss inside the USB charger turns into heat, and the unit's temperature begins to rise. First, 70 minutes after the start of the experiment, stage-one thermal throttling occurred. The surface temperature was approximately 70°C. The thermography shown earlier was the temperature at this point. In the first stage, power from C2 to C5 drops from 60W to 45W. Total output power is therefore reduced to 440W.
About 20 minutes later, stage-two thermal throttling occurred. In this stage, the C1 port drops from 48V output to 36V output. This lowers total output power to 380W. More time passed, and 180 minutes after the start of the experiment, stage-three thermal throttling occurred. The output power of the C5 port was reduced to 15W, bringing total output power down to 350W. After that, it repeatedly switched between the second and third stages of thermal throttling. That would mean 350W is the continuous power rating.
Here is the main part of the story. We will start disassembling and checking the USB charger. We've disassembled it to some extent. Here, it consists of the charger's main body and the exterior. The sheet on the exterior portion looks like a silicone-based heat-conductive sheet. It is attached on four sides, wrapping around the charger's body. It is relatively easy to peel off. It's made of a pretty soft and brittle material.
From what I can see, the heat-conductive materials are not tightly packed between the exterior and the charger. There are quite a few gaps. I think this is a major difference from small USB chargers, which are filled with silicone potting material without gaps. This caused the uneven heat distribution and temperature differences we saw in the thermography earlier. The hot area appeared in a square shape.
On the other hand, filling the available space with a highly thermally conductive gap filler probably wouldn't be feasible. Gap fillers with high thermal conductivity are quite expensive. It can be surprisingly costly! I assume it is designed this way to keep the product price down.
Next we will look at the charger itself. An aluminum-like material wraps all the way around the charger. The plate is about 1mm thick. Its role is to dissipate heat from the circuit and keep radiated noise from escaping. In the lower-end 300W version, it was made of a brass-like material. The 500W version seems to have changed materials. Aluminum conducts heat better and also has high electrical conductivity, making it excellent for electromagnetic shielding.
The aluminum was electrically connected to the circuitry on the printed circuit board. But aluminum cannot be soldered, so it is riveted to a solderable metal, and that metal is connected to the circuit by soldering. It's a pretty tough structure.
With the aluminum shield removed, you can see more resin plates underneath. Below those, it is filled with silicone-based potting material for heat conduction. As far as I can see, I think they place this side on top and pour the potting material in from here. It's pretty tightly packed. You can remove the potting material by pinching it like this. It comes off in fairly large pieces. We will peel all of it off to see the internal circuitry.
By the way, when I was looking at the thermography, this area on this side was the hottest. There must be something under this. It's incredibly tightly packed.
All the heat transfer materials have been removed. More potting material was used than I expected. This large amount of potting material came out of this USB charger. What is the mass of the potting material that was inside? 677g. Adding the weights of the four heat-conductive sheets attached to the exterior gives 761g. The main unit weighs 1,595g, so about 47% of its mass is heat-dissipating material. A tremendous amount of material is used to dissipate heat.
As we have seen, I think they are doing quite a lot for heat dissipation. Still, as you can see here, letting the heat escape is pretty difficult. In a typical USB charger, the heat dissipation path goes from the heat source through potting material to the exterior. Therefore, heat transfers well from the heat source to the outside.
On the other hand, what happens in the UGREEN? As we have seen by taking it apart, the heat path goes from the heat source through potting material, then plastic, an aluminum plate, a heat-conductive sheet, and finally the exterior. Many of these act as thermal resistance. The structure makes it difficult for heat to escape outside. In addition, the plastic, aluminum, and heat-conductive sheets are not completely adhered to each other. There were gaps in some areas, which cause even higher thermal resistance.
The USB charger we disassembled this time is a sealed type. I guess that is why it is structured this way. This is a major difference from industrial power supplies.
From here, we can break it down further. We will look at the internal circuitry. The general structure of the system is as follows: the left side is the input and the right side is the USB output. The main board here has a filter circuit, rectifier circuit, power factor correction circuit, and isolated DC/DC converter. Then there is the USB board.
The board consists of four pieces in total: the main board, the USB board, and plug-in boards with components such as the power semiconductors on them. I have two wires flying in the air here. This is wiring for connecting the secondary-side Y-capacitor and so on to the primary side. Looking at the back side, many surface-mounted components are lined up like this.
We will look at the circuits in turn. First, the filter circuit. This is a filter circuit with capacitors and inductors. For a large rated power of 500W, noise leaking out tends to be greater, so the filters are also larger. There is this white component. This is a thermostat. As we are going to see, I have the impression that the entire board is under pretty strict temperature control.
Next is the rectifier circuit. This is a circuit that converts the AC voltage coming through the filter circuit to direct current. This product does not use bridge diodes. The ideal diode circuit is made with a controller and MOSFETs. When it comes to 500W-class power supplies, using diodes would cause too much loss. Using the MOSFET on-state voltage instead of the diode's forward voltage reduces power loss.
Looking at the back side of this board, small metal pieces are surface mounted. This is partly to increase the current capacity of the copper foil. I think they are also used to improve the heat dissipation and heat storage properties of this substrate itself. In fact, these areas were also all potted with silicone resin. It's easier to understand when you look at the positions of the semiconductors on the front face. The pieces are mounted right at the semiconductor positions.
Next is the power factor correction circuit. The power factor correction circuit is the same as a boost converter circuit. This product actually contains two identical power factor correction circuits, with interleaved control to operate them alternately. It is a 500W-class circuit, so the inductors are as large as you'd expect.
Where the transformer was, there was exposed copper foil to improve heat transfer. All of these areas were also filled with heat-conductive potting material. This thermally couples the inductor to the printed circuit board.
The control IC and power semiconductors are located behind the main board. For the power semiconductors, it uses Innoscience's GaN HEMTs and SiC Schottky barrier diodes from Senguoke. Since those are for two circuits, I have the impression that they use power semiconductors quite luxuriously. There are ferrite beads that I think are used to reduce noise. I'm not sure I understand it well. Is it amorphous-like?
Then you go into isolated converters. This seems to use an asymmetric half-bridge system. It has two circuits. If you look closely, you'll see that it's designed to monitor the temperature of the transformers. There are two temperature sensors. All of these areas were potted as well, so they were thermally bonded.
The power semiconductors for two circuits are mounted on this plug-in board. It looks like this, on the front side only. These are GaN power semiconductors also made by Innoscience. Innoscience is still quite strong. In particular, I suspect there are quite a lot of examples of adoption in power supplies from Chinese manufacturers. The controller is made by Richtek, part of Taiwan's MediaTek group.
I mentioned earlier that there are two isolated converter circuits. One is used exclusively for C1 with 240W output. The other is shared by C2–C5 and A1. In terms of power, each circuit handles exactly half. It depends on the actual usage, but the load factor seems to be higher for the upper converter here, shared by C2–C5 and A1. You can see this clearly in the thermography. The area around this transformer generated the most heat.
Finally, we look at the USB board. There are inductors and electrolytic capacitors. Maybe they're polymer or solid types. These are all used in C2–C5 and A1. This is because, after making 20V on the main board, this USB board steps it down to the voltage for USB PD. The evidence for this is that MOSFETs for the buck converter are mounted here.
On the back side of the USB board, there is an iSmartWare IC with a built-in PD controller and buck converter controller. Where is the C1 controller located? It is located on the main board side here. They say this is a PD controller made by Richtek. As for C1, it uses this dedicated circuit, so there is no need for voltage conversion on the USB board. It just needs to get the CC signal. There is a trace for that.
Today I have disassembled and reviewed UGREEN's 500W USB charger. The main advantage of this charger is that it can output 240W from a single port. When you take it apart, you can clearly understand the circuitry that supports it.
How do you keep the heat down in a modern USB charger? Heat dissipation has become a challenge. In this charger, filling the inside of the body with a heat-conductive potting material thermally bonded everything together. Then the heat was transferred through the exterior to escape outside. But this is a high-capacity, sealed switching power supply. I still think it seems quite difficult to release heat.
I could tell when I was taking it apart. Considering that heat-dissipating materials occupy approximately half of the charger's mass, I believe heat dissipation must have been very difficult.
As for the charger I disassembled today, there is a purchase link in the description. If you are interested, please check it out! If you found this video helpful, please give us a high rating and subscribe to our channel! If you have any concerns, please contact us. Please leave your comments as well! Thank you for watching the video until the end.
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