On October 14th, Beijing time, the second session of Apple’s autumn new product launch event was held, and Apple’s iPhone 12 series of smart phones and a new generation of HomePod mini smart speaker products were released. Although HomePod mini still maintains the same design style compared to the previous generation product HomePod, there are big differences in product size and functional configuration.
The HomePod mini body adopts a circular shape, the surface is wrapped in a seamless mesh, and the overall height is less than 9 cm; the backlit touch panel on the top of the speaker can produce different color fluctuations according to voice interaction. In terms of functional configuration, HomePod mini is equipped with Apple’s S5 processor, built-in ultra-wideband chip, can accurately locate the latest Apple models and other smart home devices, based on a powerful ecosystem, to achieve seamless connection between multiple devices.
It also supports 360-degree audio, smart assistants, home control, combined stereo and other functions; and a new broadcast function, which can connect to Apple’s ecological equipment in real time, and transmit information to each other in the form of broadcast, which increases the use scene and interest of the product. Let’s take a look at the internal structure of this smart speaker!
| 1. Apple HomePod mini smart speaker unboxing
The packaging box design is still relatively simple, with only the rendering of the product appearance on the front.
There is the product name Apple HomePod mini on the packaging and the back. The mini word uses gradient colors and is designed with an audio vibrating effect.
The top of the box is designed with a top view rendering of the speaker. The backlit touchpad can produce different color fluctuations based on voice interaction.
The bottom information includes the introduction of functions such as HomePod mini intelligent assistant, home control, combined stereo, broadcast, etc.; adapted models, and some product parameters. Commodity name: Smart speaker; Model: A2531; Input: 100-240V~50-60Hz, 0.5A made in China.
The contents of the box include speakers, power adapters and product manuals. The power input line and the speakers are integrated.
The power adapter adopts USB Type-C interface.
The information on the power adapter has a maximum output power of 20W, Model: A2244, made in China; Input: 100-240V~50-60Hz, 0.5A; Output: 5V⎓3A or 9V⎓2.22A; Manufacturer: Flextronics Power (Dongguan) Co ., Ltd.;; power adapter EMC 3596; SN: C4H04060WYTPF4MBL.
Using ChargerLAB POWER-Z KM001C to detect the output protocol of Apple’s 20W PD fast charging, it shows that only Samsung 5V/2A, DCP protocol, and USB PD2.0 fast charging protocol are supported.
In addition, PDO shows that the USB-C port has two fixed voltage levels of 5V3A and 9V2.22A.
The front appearance of the speaker, the wire is coiled at the bottom of the speaker by a paper cable harness.
The back of the speaker is the location of the wire interface.
The wires are stored in a paper cable harness, which conforms to Apple’s environmental protection concept.
The outside of the wire is protected by a braid, which improves the service life and texture.
USB Type-C charging interface.
The top of the speaker is a touchpad with “+, -” volume signs, which can produce different color fluctuations according to voice interaction under working conditions.
There is Apple LOGO at the bottom, product model: A2531, American Apple, made in China, input: 9V⎓2.22A, product name: smart speaker.
52audio used the ChargerLAB POWER-Z KM001C portable power tester to test the power supply of the Apple HomePod mini smart speaker, and the standby power was about 0.60W.
Apple HomePod mini and Apple HomePod size comparison.
Top view of the size comparison of Apple HomePod mini and Apple HomePod.
According to 52audio’s actual measurement, the weight of the Apple HomePod is about 2496.4g.
Apple HomePod mini weighs only 350.2g.
| 2. Apple HomePod Mini smart speaker teardown
Coming to the disassembly part, first start with the base and open the base cover fixed by the double-sided tape and bayonet positioning structure.
A list of the internal test structure of the cover, the gray cover material is slightly softer and the black ring-shaped hard reinforced plastic is used. The use of soft material at the bottom is to absorb the vibration noise generated by the contact surface when the speaker is working.
The plastic plate of the fixed base is fixed on the plastic frame of the fixed woven net by three screws.
Remove the screws and remove the plastic plate holding the base.
Three screws are equipped with a thicker rubber cushion.
The front surface of the plastic plate of the fixed base is covered with a layer of double-sided tape.
The back of the plastic plate of the fixed base has a snap structure in the middle. The three large holes around are screw holes and the small holes are tuning holes to ensure air circulation in the cavity.
The plastic frame for fixing the mesh is fixed to the inner cavity by a screw.
Remove the screws and remove the plastic frame.
The front of the plastic frame to fix the mesh.
There are two curved cushion foams on the back.
The front cushion shark fin design is connected with the base to enhance the sound absorption effect of the speaker.
The curved foam pad is fixed to the cover by glue.
On the back of the sound guide cone of the speaker, the middle position of the three holes is the screw socket, and the two sides are the tuning holes.
There is also a layer of woven net wrapped inside the woven net.
The appearance of the internal cavity.
The strip sound holes on the cavity are arranged in an oval shape, and the passive diaphragm unit, which is also oval, can be seen inside.
Fence type sound hole at the base of the cavity.
The fixing screws on the cavity are filled with rubber plugs to make the sound box as a whole.
Screw hole rubber plug.
The cavity has a microphone opening and is covered by a dust-proof net. The whole machine has a total of four microphones to form a pickup array for picking up voice commands and broadcasting functions.
The woven mesh on the top of the speaker is fixed by the touch cover. From this angle, you can see that there is one behind the two microphone pickup holes. There are four microphones in the speaker, and the fourth is at the bottom of the speaker.
Rubber plugs with 8 screw holes.
Open the top cover, and the touch sensor cover is connected to the motherboard through a cable.
The backlit touch panel is fixed to the top cover by screws.
A groove is arranged at the junction of the cover plate and the cavity, and a sealing sponge pad is placed in the groove.
Remove the screws and take out the backlit touch panel. The end of the woven net and the cavity are fixed by glue.
Inside the backlit touchpad.
The outer side of the backlit touch panel, and the white area in the middle is the light leveling panel.
A sealing rubber ring is arranged on the plastic frame.
Use light-shielding tape to seal around the homogenizing plate to prevent light leakage.
Display of the working status of the backlit touchpad.
On the top of the cavity, the white area in the middle is the light guide structure of the RGB LED light group.
The front of the light guide structure.
The back of the light guide structure is fixed to the main board by double-sided tape and two cylindrical clamping posts.
Thick sponge cushions are arranged on both sides of the light guide structure connected with the touch backlight board.
There are 19 RGB LED lights in the middle of the components on the main board to form an LED array for interactive control feedback.
These two six-pin screws are the positive and negative terminals of the speaker unit, which not only fix the wiring terminals but also fix the main board. A similar design has the same way of fixing the tweeter on HomePod.
The microphone unit is connected to the motherboard through a flat cable socket.
The foam cushion on the main board improves the shock absorption effect.
The power input wire is connected to the motherboard through a flat cable socket.
Remove the cable plug and take off the motherboard for disassembly.
In the internal structure of the cavity, a heat-dissipating metal structure is arranged at the transfer position of the main control chip of the main board on the plastic frame, and a thermal conductive silicone grease is provided on the metal plate.
The contact point for connecting the speaker to the motherboard.
Take out the speaker unit.
The metal structure in the cavity is used to dissipate the heat of the motherboard chip, which effectively reduces the temperature of the motherboard chip and improves the stability during work.
The vibration cancellation passive radiator designed by Apple, one on the left and one on the left, improves the low-frequency volume and ductility, and presents a 360-degree surround sound field.
There is a square cushion on the back of the speaker.
The internal structure of the sound cavity.
Sound cavity guide cone.
Power input wire socket.
A microphone unit can be seen from the air outlet fence.
A single microphone unit is located in the independent cavity.
This part of the sensor assembly uses a rubber seal.
Disassemble the microphone unit.
The outer layer of the MEMS microphone is wrapped with a lot of glue.
The microphone opening on the back is covered by a dust-proof net.
The MEMS microphone cannot be removed because the hard glue is too strong.
The end of the microphone cable is equipped with an FPC antenna, which is fed through a metal frame.
Remove the metal frame.
The IC of silk screen EH.
The IC of silk screen D8 is used for signal receiving function.
The appearance of the speaker.
Conductive cushioning sponge pad on the T iron on the back of the speaker.
The speaker wires have full and round solder joints.
The front of the speaker.
The edge of the speaker is embossed and dipped.
Components on the front of the motherboard.
Components on the back of the motherboard.
There are a total of four filter capacitors of two specifications on the front of the motherboard.
1000μF 25V filter capacitor, from nichicon, 25V 150μF filter capacitor from daily chemical on the right, the bottom of the capacitor is fixed with black glue.
There are 19 RGB LED lights in the middle of the back of the motherboard, surrounded by three on-board bluetooth antennas, three black round rubber rings for microphone openings, cable sockets and multiple ICs.
RGB LED lights.
TI LP5030 RGB LED driver. The LP503x device is a 30 or 36 channel constant current LED driver. With 29kHz, 12-bit PWM generator for each channel and independent color mixing and intensity control of the channel/module, it can achieve a vivid LED effect with zero audible noise. Users can benefit from the device’s ultra-low shutdown Iq power-saving mode, and designers can easily code software with the three programmable groups (RGB) of the LP503x.
TI LP5030 details.
Silk screen 3 90 IC.
The power conversion circuit is reinforced with hard glue.
The power conversion circuit, IC is also reinforced with hard glue.
TI INA199 bidirectional current detection IC, the right side is the current-sense resistor.
TI TPS55340 regulator is a monolithic non-synchronous switching regulator with an integrated 5A, 40V power switch. This device can be configured into a variety of standard switching regulator topologies, including boost, SEPIC and isolated flyback. With a wide input voltage range, it can support applications where the input voltage is provided by multiple batteries or 3.3V, 5V, 12V and 24V regulated power rails.
TI TPS55340 detailed information.
2.4G onboard bluetooth antenna.
5.8G onboard bluetooth antenna.
The components on the front of the motherboard are densely packed but neatly arranged. Conductive cloth is arranged around the main control chip and is connected with the heat dissipation metal plate. There is also a metal shield covering the lower area.
T TPS62130 step-down converter, TPS6213X series is a simple and easy-to-use synchronous step-down DC-DC converter, optimized for high power density applications. The switching frequency of the device is typically up to 2.5MHz, allowing the use of small inductors, using DCS-Control™ topology technology to provide fast transient response and achieve high output voltage accuracy.
TI TPS62130 details.
Wireless module with silk-screened QR code.
ADI SSM3582A 2×31.76W, digital input, filterless stereo class D audio amplifier. Compared with other D-class architectures, the proprietary spread-spectrum Σ-Δ modulation scheme supports direct connection to speakers and ensures the highest analog performance while reducing radiated emissions. The optional ultra-low electromagnetic interference (EMI) mode can significantly reduce radiation above 100 MHz, thereby increasing the length of the speaker cable.
The audio is transmitted digitally to the amplifier to minimize the possibility of signal damage in the digital environment. The amplifier provides excellent analog performance with a signal-to-noise ratio of 106 dB and a low total harmonic distortion + noise (THD + N) of 0.004%.
SSM3582A is powered by a single 4.5 V to 16 V power supply and can continuously provide 2×15 W rms for 8 Ω and 4 Ω loads with a total harmonic distortion (THD) of less than 1%. The high-efficiency modulation scheme maintains excellent power efficiency over a wide impedance range: 93.8% when the load is 8 Ω, and 90.6% when the load is 4 Ω. Output pulse optimization can maintain high performance at impedances as low as 3 Ω/5 μH, allowing it to be used for extended bandwidth tweeters.
ADI SSM3582A detailed information.
TI TPS60151 140mA output charge pump.
Metal contacts connected to speakers.
Two FP 6H ICs.
Silk screen DV H5 IC.
Silk screen NRBKO IC.
Silkscreen 6DOZ IC.
The IC of silk screen B8A78.
WiFi+bluetooth module with silk screen QR code USI 339M00095.
ON Semiconductor NSR20F40NXT5G 40V2A Schottky diode.
ON Semiconductor NSR20F40NXT5G details.
TI CD3217B12 USB-PD controller.
The memory of silk screen 8N038.
Open the shielding cover, there are two ICs and a crystal inside.
SKYWORKS SKY66404 2.4G bluetooth front-end module.
SKYWORKS SKY66404 detailed information.
Nordic N52833 advanced multi-protocol SOC, bluetooth Low Energy (bluetooth Low Energy /bluetooth LE), Thread, ZigBee and 2.4 GHz private wireless connection solutions. The radio includes bluetooth 5.1 direction finding function and can operate effectively in the temperature range of -40 to 105°C.
N52833 uses a 64 MHz 32-bit arm Cortex-M4 processor with FPU, which contains large-capacity flash memory (512 KB) and RAM (128 KB) memory. It is suitable for a variety of commercial and industrial wireless applications including professional lighting, asset tracking, smart home products, advanced wearable devices and gaming solutions.
Details of Nordic N52833.
Many components and ICs are arranged neatly in the frame constructed by conductive mesh. On the left is the power IC, and on the right is the S5 processor.
Silkscreen OCTA1 IC.
Two ICs with silk screen W7 0cA.
Apple customized silk screen 338S00553-A0 power management IC.
Apple Apple S5 processor. Supports computational audio technology, can process complex algorithms in real time, and provide balanced and optimized sound quality.
There are a total of three MEMS microphones around the main board, and an independent cavity microphone forms a pickup array.
All internal components of the Apple HomePod Mini smart speaker.
| 3. 52audio summary
The Apple HomePod Mini smart speaker adopts a round compact body in the design, and is double-wrapped with seamless mesh. The top is equipped with a backlit touch panel, which can display different color fluctuations according to voice commands under working conditions. The overall appearance design inherits the style of the previous generation product. It also supports the operation of 360-degree audio, intelligent assistant, home control, combined stereo, etc., and also adds the broadcasting function, but the weight is only about 1/7 of the previous generation product. . The disadvantage is that although the volume is small and exquisite, there is no built-in battery unit, which reduces the portability to a certain extent.
The internal structure maintains Apple’s consistent standard, exquisite workmanship, interlocking, and careful handling of details. The speaker base is composed of three components for fixing the non-slip base and fixing the net. The shark fin cushion design at the connection position of the components can improve the shock absorption effect.
The internal main body is divided into a three-layer structure of upper, middle and lower, followed by a backlit touch panel, a main board, a metal heat sink, a sound cavity, and a sound guide cone. The component connection part is equipped with a thicker cushion. Some cushions also use a “) (” shape to improve the shock absorption effect. The sound cavity includes a full-frequency drive unit, and two Apple-designed vibration cancellation passive radiators on both sides to enhance low-frequency extension and 360-degree surround sound field .
On the motherboard, three antennas are equipped around to improve connection stability; three microphone pickup units with an inward microphone to isolate the sound from the speaker and improve the voice detection ability during music playback; 19 RGB LED lights The LED array provides the light source for the backlit touch panel, the TI LP5030 RGB LED driver is used for color mixing and intensity control, and the TI TPS55340 voltage regulator; the main control chip is the Apple S5 processor, which provides for the Apple ecosystem while processing complex algorithms stand by.
It is also equipped with a Nordic N52833 ARM Cortex-M4 processor to assist it, supporting bluetooth 5.1, Thread, ZigBee and 2.4 GHz wireless connection solutions; audio processing uses ADI SSM3582A Class D audio amplifier, power management IC Apple customized 338S00553 chip, SKYWORKS SKY66404 2.4G bluetooth front-end module, and TPS6213X synchronous step-down DC-DC converter.