Previously, the charging head network has brought you the detailed evaluation of this charger, and disassembled the attached 100W usb-c to usb-c cable. Now, Xiaobian continues to share the internal disassembly of Xiaomi's 90W USB PD charger.
One, Xiaomi 90W USB PD fast charger appearance
The appearance of Xiaomi 90W PD charger is the same as before in Xiaomi style, with white and bright surface shell and single usb-c port design. As seen from the above figure, the surface of the shell is very simple and clean without any brand and character marks.
Generally speaking, the charger is square, but there is also a round side between the squares. At the junction of waist surface, top surface and bottom surface, fillet transition is carried out, so that the charger as a whole will not be too rigid, and the hand feeling of holding can be balanced.
Take another look at the side of the pin. The shell on this side is made of matte gray material, with relevant parameters of millet logo and charger printed. In addition, this millet 90W PD charger is designed with folding pin, which is convenient for storage and carrying.
Let's take a look at the specific parameters of Xiaomi 90W PD charger:
Input: 100-240V ~ 50 / 60Hz 1.6A;
Manufacturer: Beijing Tianmi Technology Co., Ltd.
Beijing Tianmi Technology Co., Ltd. is the ecological chain company of Xiaomi laptop computer.
Xiaomi 90W PD charger weighs about 220g.
In terms of volume, Xiaomi 90W PD charger is slightly larger than Xiaomi 45W and 65W PD chargers.
Use chargerlab power-z kt001 to detect the fast charging protocol of the charger, which shows that USB DCP, qc2.0 and qc3.0 charging protocols are supported.
The PDO message of usb-c interface shows that the charger supports USB pd3.0 fast charging protocol, and has four voltage levels of 5V / 3a, 9v3a, 12V / 3a, 15v3v and 20V / 4.5a, with the maximum power output of 90W.
2、 Disassembly of Xiaomi 90W USB PD fast charging charger
Open the shell from the pin side of the charger. The shell is welded with ultrasonic wave. The inner side of the pin is wrapped with Marla tape for insulation.
Take out the internal circuit board, and use the copper sheet on the front of the circuit board for heat dissipation.
The back of the circuit board is also covered with a large area of copper heat sink.
Remove the front heat dissipation copper sheet, and fill silica gel between components to fix components and conduct heat.
At the back of PCB.
Remove the front filled with silica gel and see the basic form of each component.
The input terminal is equipped with safety capacitance, common mode inductance, input rectifier bridge, film capacitance and other devices.
Input delay fuse, specification 3.15A250V.
Safety gauge x capacitance, 0.47uf.
The input cable is sheathed with a magnetic ring to suppress interference.
The common mode inductor is labeled and produced by Liteon.
The common mode inductor is labeled and produced by Liteon.
Close up of input rectifier bridge, g805b.
Close up of film capacitance, 0.68 μ f 450V.
Two film capacitors of the same type.
The input end is equipped with a PFC boost inductor, which is wound with Marla tape on the side and grounded with copper foil.
Switching tube of PFC boost circuit from Ansemi, FCPF190N65S3. with a voltage of 650 V and a resistance of 190 mΩ.
Details of fcpf190n65s3.
The input filter electrolytic capacitor is laid horizontally to save space. On the right is the heat sink of the primary switch tube.
Input filter electrolytic capacitor, 420v 82uf, daily chemical KMG, heat resistant 105 ℃.
The switch transformer is wrapped with insulating tape for insulation. From the label information, we can know that the transformer is from Liteon Guangbao.
I-inductor, wrapped in heat shrinkable tube.
PWM chip power supply capacitance, specification is 100V15uF.
There is a small PCB board on the side, Liteon, Guangbao OEM.
Two L217 optocouplers and a protocol chip are arranged on the back of the vertically mounted protocol panel.
Close up of two optocouplers, one of which was damaged during disassembly.
The USB PD fast charging protocol chip adopts Weiquan wt6615f. This is a USB PD controller that supports USB PD 3.0 specification and Qualcomm qc3.0 and qc4 technology, and supports DFP downlink port (source) charging application. The highly integrated wt6615f can be used in adapter, car charger, mobile power supply and other equipment. At the same time, wt6615f supports the latest programmable power supply (PPS) specification of USB PD, which is generally used for direct charging scheme of mobile devices.
Detailed specification of wt6615f.
The output USB-C interface next to the protocol panel is vertically welded on the main PCB board, and the left side of the interface is the output filtered common-mode inductance.
Close up of usb-c interface, wrapped in all metal shell, very strong.
Output filter common mode inductance.
Between usb-c interface and common mode inductor is an output VBUS switch tube, Fuding ap3p3r0, PMOS, withstand voltage 30V, and lead resistance 3M Ω.
Details of Fuding ap3p3r0.
After removing the protocol panel, a secondary synchronous rectifier MOS, Nexperia PSMN6R9-100YSF, can be seen in the USB-C interface attachment. 100V withstand voltage,7mΩ resistance, LFPAK56 package.
Nexperia psmn6r9-100ysf details.
The USB-C port output filter uses two solid-state capacitors in parallel, the specifications are 470μF 25V, and there are two Y capacitors next to it.
One of the Y capacitors.
another y capacitor close-up.
PFC boost rectifier.
PCB back view, only primary circuit of switching power supply.
An NXP PFC controller, model tea19162t, is used for PFC boost.
NXP Enzhipu TEA19162T specification details.
PWM main control chip, NXP 19363lt, next to the primary switch MOS tube.
NXP Enzhipu 19363LT specification details.
Primary switched MOS tubes from infineon Infineon, IPL65R230C7,650V withstand voltage,230mΩ conductance, ThinPAK8×8 package.
Infineon ipl65r230c7 details.
Two optocouplers are used for voltage detection and overcurrent protection.
Next to the optocoupler is the secondary synchronous rectifier controller, also provided by NXP, model tea1993ts.
Specifications of NXP tea1993ts.
Disassembly summary of charging head network
Through the dismantling of the charging head net, it was found that the charger added the PFC power factor correction circuit at the input, and the power supply part used the full set of NXP Enzhipu's controller, the protocol part used the Weian WT6615F as the USB-CPD controller, compatible with the QC3.0, QC2.0 fast charging protocol, and the internal use of the large line factory switch tube and capacitor. This product in addition to the material is very solid, in the workmanship is also very careful, components layout orderly, and the use of a large number of silicone fixed and heat conduction; pcb module on both sides of the use of large area copper uniform heat dissipation, to avoid long-time high-power work, local overheating, improve the user's use experience.