At the same time, this speaker is also the super terminal of HarmonyOS system HarmonyOS system, which supports the connection of Huawei mobile phone, tablet and Android mobile phone, seven monochrome and one mixed color, intelligent lighting effect and smart home control. At the same time, it also supports two speakers to form wireless stereo, which can be used with smart screens and is an important part of Huawei's smart home.
The charging head network has a power adapter for this speaker. The power supply is 65W power, 24V2.7 1A output, and the cable is fixed. Let's take a look at the disassembly of this power supply.
The body style of this adapter is very classic Huawei original charger style, and the shell has been highlighted.
Small concave surfaces are designed on the front and back of the fuselage, which is convenient for users to plug and use.
Equipped with fixed national standard pins, arranged on one side.
The input shell is printed with adapter parameters.
Model: HW-24027 1C00
Input:100-240v ~ 50/60hz1.5a.
Output: 24V2.7 1A
Manufacturer: Shenzhen Hangjia Chi Yuan Electric Co., Ltd.
The adapter has passed CCC certification and Grade VI energy efficiency certification.
In addition, the adapter is equipped with DC round-headed output cable.
The connection between the cable and the fuselage has been treated with anti-bending.
The bent end 90 is designed to facilitate the layout of the speaker.
The height of the adapter body is measured as 69.63mm..
The width is 69.68 mm.
The thickness is 29.2 mm.
In addition, the measured cable length is about1.5m. ..
The body size is equivalent to Apple's 60W charger.
The size of the hand is intuitive.
The total weight of the adapter belt is about 241g.
After having a basic understanding of the appearance, size and parameters of the original 65W adapter of Huawei Sound X 202 1 speaker, the following charging head network will disassemble it in detail. Let's take a look at the specific materials and workmanship of this adapter.
Disassemble the shell from the pin side of the charger, and there is foam buffer inside the shell. The input pin is connected to the PCBA module through wires, and the solder joints of the wires are bonded to strengthen insulation.
PCBA module of charger is completely wrapped by heat sink and fixed with buckle.
The radiator on the back of PCBA module is fixed by fastening and welding.
Remove the heat sink, coat white glue between the transformer and the components for heat conduction, and paste insulation sheets and heat conduction pads between the back of the circuit board and the heat sink to evenly dissipate heat.
The lead wire at the input end is pressed to the terminal before welding and reinforced with glue.
Close-up of the thermal pad on the back of PCBA.
The measured module length is 65.72 mm.
The width is 66.2 mm.
The thickness is 25.22 mm.
The general layout on the front of PCB shows that the input rheostat is connected in series with the temperature fuse to protect the input from abnormal overvoltage, and components such as slow-melting fuse, * * * * mode inductor and NTC thermistor can be used. Both the primary switch tube and the secondary Schottky diode have heat sinks, and the output is filtered by solid-state capacitors.
There are many silica gel pads on the back of PCBA to support the gap between the back radiator and PCB.
On the back is the main PWM controller, optocoupler for output voltage feedback and corresponding peripheral components.
Through observation, it is found that this power adapter adopts flyback switching power supply architecture design and outputs fixed voltage. Considering the speaker's high output voltage, low current and discontinuous power supply, Schottky rectifier is adopted. In addition, the varistor at the input end of the power supply is connected in series with a temperature fuse for overheating protection, and the internal large-area heat dissipation design is suitable for long-term plug-in operation. Let's learn about each device from the input.
The slow-melting fuse at the input end of the power supply comes from Beite Electronics, and the fuse specification is 3. 15A 250V.
The varistor comes from Sert, SFV 10D56 1KT+0KT. In case of overvoltage, the resistor will break down, cut off the fuse and protect other circuits inside the charger.
Close-up of temperature fuse, with ATCO alloy type, Y series, rated current 5A, rated working temperature 130. It is fixed with heat shrinkable tube of rheostat to monitor the temperature of rheostat, and cut off the connection between rheostat and circuit when the temperature is too high.
NTC thermistor, model 10S2R5M, is used to suppress the surge current when the adapter is inserted and prevent fire.
Safety X2 capacitor, 0.47μF, used to suppress differential mode interference.
* * * mode inductance adopts magnetic winding system, and insulation is strengthened between two coils with insulation board, and insulation is strengthened at the bottom.
The input alternating current enters the rectifier bridge after passing through the fuse and EMI filter circuit and is converted into pulsating direct current by the rectifier bridge.
The first-stage filter capacitor comes from Ai Shi Ai Hua, and the HS series can withstand high temperature165438+450 V120 μ f.
The power capacitor specification of the main control chip is 50 V10 μ f f.
The main controller of switching power supply is screen printed SHt, which is packaged in SOT23-6.
The main switch tube comes from NMOS Toshiba TK 13A65U, with650V withstand voltage and 0.32Ω conductance, and is packaged in 650V. The switch tube is fixed on the heat sink to enhance heat dissipation.
Close-up of high-voltage ceramic capacitor of flyback RCD absorption circuit, 10nF, withstand voltage 1000V.
Close-up of transformer, tightly wrapped with insulating tape.
The output Schottky rectifier comes from Wei Ping, PSM30U 150CT, 30A, withstand voltage 150V, and is used for output rectification of the adapter. Using Schottky diode here can get faster transient response.
EL 10 19 optocoupler for feedback output voltage.
Close-up of two y capacitors.
Because the output voltage of the adapter is 24V, a solid capacitor with 35V withstand voltage is selected for filtering, and the first one is 820μF 35V.
The other solid capacitor is 1000μF 35V.
The output filter inductor adopts double-wire winding, and an insulating plate is fixed at the bottom of the magnetic ring, which is isolated from PCB.
Close-up of output line, coaxial structure and fixed output line by welding cable card on PCB.
All dismantled, let's have a family photo.
Generally speaking, smart speakers are usually turned off 24 hours, which is very convenient to use at any time. According to the application habits of smart speakers, Huawei optimized the power adapter of Sound X 202 1. First of all, the input rheostat and the temperature fuse are fixed together with a heat shrinkable tube, so that the power supply can be cut off when the rheostat is abnormally overheated to ensure safety.
Large-area heat sinks are used inside, which is helpful for heat dissipation during long-term high-power work, and large-area metal heat sinks are used for switch tubes and output rectifier tubes, which can effectively dissipate heat. In view of the unstable load of loudspeaker products, Schottky diode is used in power supply instead of synchronous rectifier, which is widely used at present, and better transient response can be obtained.
When disassembling, it was also found that this power supply was produced by Hangjia, a big manufacturer in the industry. Toshiba primary switch tube and Wei Ping Schottky rectifier tube are used internally. The capacitor adopts AISI Aihua high temperature resistant series, which effectively ensures the reliability of power supply during the product life cycle and meets the use requirements of 24-hour power supply.