Recently, Xiaomi updated their 120W GaN fast charger from USB-A to USB-C.
It only takes about 15 mins to fully charge some Xiaomi smartphones,
such as the Redmi Note 11 pro+.
Today, ChargerLAB will teardown this 120W GaN fast charger.
By the way, we also tore down the dual-port 65W fast charger of Xiaomi.
You can click the upper right corner to take a look.
After opening the box, here is the charger and cable.
The dual USB-C ports are orange.
It can support 6A current.
The length of the cable is 1 m (3’3.37”).
This charger is similar to the previous generation.
It adopts glossy shell and is printed with “GaN” and “120W”.
The color of USB-C port is the same as cable’s.
Flip to the other side. We can see the model is MDY-13-ET.
It supports input of 100-240V~50/60HZ 1.7A.
We can clearly see that the new model is slightly smaller.
Let’s see its size.
The length and width are 55mm (2.17 inches).
The height is 28mm (1.1 inches).
And weight is about 138g (4.87 oz).
Use ChargerLAB POWER-Z KT002 to test the protocol.
It supports Samsung 5V/2A, DCP, and QC2.0, QC3.0, PD3.0.
But the maximum power of PD protocol is 65W.
And it supports four fixed PDOs of 5V3A, 9V3A, 15V3A, 20V3.25A.
The 20V 6A 120W is Xiaomi’s private protocol.
Next, let’s tear it down.
The entire PCB module is filled with thermal adhesives.
Here is a graphite thermal pad on the right.
The AC wire is connected to the plug.
After cleaning up the thermal adhesives, we can see lots of components are on the front.
The planar transformer is on the back, used for reducing the size and thickness.
ChargerLAB found that this charger can power the QR flyback switching power supply after PFC boost.
The output voltage will depend on the load and be controlled by protocol chip.
Remove all the components on the front.
There is a rectifier bridge, a GaN IC, and a protocol chip.
Then, let’s analyze the components one by one.
The input fuse is insulated with heat-shrinkable tube.
The varistor is used for input overvoltage protection.
It will turn on when the AC input exceeds the safe range.
The surge suppressor can reduce the current surge of the power supply.
Common mode choke is also insulated with heat-shrinkable tube.
The other common mode choke is wound with flat copper tape.
Safety X capacitor is 0.33μF.
The input bridge rectifier is marked with LMB10L30.
Another same bridge rectifier is on the front, used to dissipate heat evenly.
Those are two film capacitors, the first is 1μF 450V, and the other is 0.68μF 450V.
The toroidal-core inductor is used for filtering.
The input PFC controller comes from Silergy SY5072B.
The built-in boost converter uses quasi-resonant switches to achieve
high efficiency and optimized EMI performance.
The switching transistor of PFC boost comes from Navitas NV6134.
This is a GaN IC with highly integrated drive and protection circuit.
It also adopts a larger pad for better heat dissipation performance.
This small cube is a PFC boost inductor.
This is a fast recovery diode, marked with ES5JCR and used for PFC rectification.
Here is a diode, used to charge the input electrolytic capacitor.
And the input electrolytic capacitors come from SAMXON.
Three of them are 400V 15μF. The other one is 400V 22μF.
The power supply capacitor of master control chip comes from CapXon.
Specs is 100V 10μF.
And the master control chip comes from ON Semiconductor NCP1342, a high-frequency
quasi-resonant flyback PWM controller.
It integrates active X2 capacitor discharge feature
and supports external thermistor for overheating protection.
The primary thermistor is in the lower-left corner, used to detect the temperature.
Because of the planar transformer, some components are on the PCB of the planar transformer,
which can improve the power density.
This GaN IC comes from Navitas NV6134 and is used for primary switching power supply.
The synchronous rectifier controller comes from MPS, model is MP6908A.
It supports operating modes of DCM, CCM, QR, ACF, and the highest operating frequency is 600KHz.
It also supports synchronous rectifiers driven by standard voltage and logic voltage.
The synchronous rectifier adopts Vanguard VSP003N10H, which adopts PDFN5*6 package
100V, 3.8mΩ.
It can be driven by 10V logic voltage.
The solid capacitor for output filter comes from BERYL
Two of them are 470μF 25V.
Another solid capacitor also comes from BERYL.
25V 470μF.
Those two EVERLIGHT optocouplers are used for feedback circuit of output voltage.
The protocol chip comes from Injoinic IP2729, which is Xiaomi’s customized model.
So, it can support Xiaomi’s private protocol.
The output VBUS MOSFET comes from Vanguard VS3698AE,
which adopts PDFN 3333 package
30V, 3mΩ.
Finally, the USB-C port is also customized.
Well, that’s all components of this charger.
The 20V 6A 120W is still Xiaomi’s private protocol
and can only be activated in specific models.
It also supports USB PD protocol,
but the maximum power is 65W.
So, if you have a Xiaomi phone that supports and want to upgrade to dual type-c cable，
you can consider this charger.
Ok, that’s all for today’s video.
If you wanna see the teardown of other Xiaomi fast chargers,
you can click the corners to take a look.
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See you in the next video. Bye.