Disassembly Report: FiiO BTR3K Bluetooth Audio Receiver
mainstream mobile phones gradually cancel the 3.5mm audio interface, the situation that only one of charging and listening to songs can be selected is really a headache for users. Some users choose to use Bluetooth headsets and true wireless headsets instead of the original wired headsets, while some users still have higher requirements for sound quality, so they will choose AMP headsets power amplifiers instead.
FiiO Feiao is an innovative enterprise focusing on portable audio products such as lossless music players, headphone power amplifiers, HiFi headphones, etc. I love audio network has been disassembled before.Fiio Feiao μBTR Bluetooth Audio Receiver,FiiO Feiao UTWS1 True Wireless Bluetooth Receiver.
This time I love audio network to disassemble is the BTR-3K balanced HiFi Bluetooth earpiece released by Feiao some time ago. It is small in size and adopts double-sided 2.5D glass design. The main control chip is Qualcomm CSR8675, which supports Bluetooth 5.0 and LDAC/aptX HD and other high-fidelity Bluetooth coding. Let's take a look at the internal structure through our detailed disassembly ~
1. FiiO Feiao BTR3K Bluetooth Audio Receiver Unpacking
packaging box is relatively simple, and the BTR3K on the rendering picture is close to the physical size and very small. The top of the packaging box is the certification of FiiO Feiao's brand Logo and HiRes Audio Wireless, and the bottom is other certification information of this product, including Bluetooth certification, support for Qualcomm aptx HD, LDAC, SBC, AAC and various Bluetooth coding formats. Product model "BTR3K Bluetooth Headset Power Amplifier".
box is the brief information of the product.
the items in the packing box, a Feiao BTR3K Bluetooth audio receiver, an independent back clip, an attached Type-C interface wire, a lanyard, tips and introduction guide, etc.
needs to be used with the back clip.
can charge BTR3K, support charging while using, and can also be connected to a computer.
.
back clip can be attached to the belt or carry-on bag.
Feiao BTR3K adopts the design of aluminum alloy middle frame and 2.5D transparent glass before and after popular on mobile phones. It looks very delicate and cannot help but want to film it.
BTR3K is also very round.
, the certified gold label of HiRes Audio Wireless, model: BTR3K Bluetooth headset power amplifier. Input: 5V ⎓ 500mA.
A close-up of the Type-C interface.
the side button of Feiao BTR3K. From top to bottom are the power button, microphone opening, multi-function button (pause/play/pairing and other functions), and volume adjustment button.
BTR3K has a 3.5mm audio interface and a 2.5mm balanced audio interface at the bottom.
BTR3K has a FiiO Logo and status indicator on the front. Different colors represent different audio decoding. For example, blue is SBC, aptX is purple, LDAC is white, etc. can be seen at a glance.
I love audio network adoptionChargerLAB POWER-Z KM001Cconducted a wired charging test on Feiao BTR3K with a charging power of 1.6W.
2. FiiO Feiao BTR3K Bluetooth Audio Receiver Disassembled
heating Feiao BTR3K, the front and rear glass panels can be removed.
, the middle is slightly higher than the surrounding, forming a groove to facilitate embedding in the middle frame and improve the airtightness.
the close-up of the outside of the front and rear glass panels, 2.5D curved glass is very helpful to improve the texture.
the light guide column at the indicator position.
Feiao BTR3K back circuit, you can see all the interfaces, keys and batteries.
The front circuit board is fixed in the housing by the back screws, and the Bluetooth antenna is directly connected to the housing.
remove all fixing screws and remove the motherboard and battery.
aluminum alloy middle frame.
is opened.
side keys are made of plastic.
motherboard, mainly Bluetooth receiver and decoder circuits.
The light emitted by the RGB LED indicator is reflected and transmitted to the light guide column and seen outside.
Shengbang micro SGM3712 switch is used to balance the output switching of the interface and the 3.5mm interface.
22.5792MHz/24.576MHz double crystal oscillator design provides clock signals at different sampling rates for DAC.
Feiao BTR3K uses two Asahi Asahi AK4377A DACs and two independent mono DACs to obtain higher stereo separation and support balanced output. The maximum output power is 60mW and the signal-to-noise ratio is 125dB.
Asahi Kasei AK4377A details.
TI Texas Instruments TPS82740A MicroSIP buck converter module, using switch mode buck, module integrated inductor, maximum output current 200mA.
TI texas instruments TPS82740A details.
main control chip is Qualcomm CSR8675, which supports Bluetooth 4.2 dual-mode when it is released. The firmware can be upgraded to Bluetooth 5.0 later. This time, Feiao BTR3K uses Bluetooth version 5.0 and supports Qualcomm aptX/aptX HD/aptX low delay, AAC, SBC and LDAC audio encoding formats.
Qualcomm CSR8675 supports analog and digital microphones; built-in high-pass Kalimba DSP,120MHz clock frequency; no external components are required, and 200mA charging current can be provided for the built-in lithium battery. In addition, CSR8675 also supports Qualcomm cVc 8.0 call noise reduction technology, which can provide clear call function for BTR3K.
As far as I love audio network dismantling,products of BOSE, SONY, magic, rambler, vivo and other brands have adopted Qualcomm solutions in large numbers..
Qualcomm CSR8675 data map, add 5.0 to the Bluetooth version on the right.
close-up on the back of the motherboard, there are many test points.
3.5mm audio interface and 2.5mm balanced audio interface.
micro-motion key, patch via welding.
laser carved MB23 RLLLR MEMS silicon wheat for call function.
Weian WP3881 Type-C input overvoltage protection switch, with a maximum withstand voltage of 28V, used to protect internal components.
Details of Weian WP3881.
battery protection circuit.
battery information, SUNDA Shenzhen xingnengda battery co., ltd, model 621733, rated voltage 3.7V, rated capacity 330mAh/1.2Wh.
to dismantle family photos.
I Love Audio Network Summary
FiiO Feiao BTR3K continues the appearance characteristics of Feiao BTR series Bluetooth audio receiver. It is very small in size. The use of aluminum alloy middle frame and double 2.5D curved glass also makes the product very textured. The front multi-color indicator can more intuitively see the Bluetooth coding format being used.
Compared with μBTR, which I love audio network dismantling before, BTR3K uses an external back clip, which makes the body feel better. However, the NFC fast pairing function is also canceled, which has both advantages and disadvantages. In comparison, BTR3K is a little more troublesome in Bluetooth repairing.
In terms of internal circuit, FiiO Feiao BTR3K main control chip is a high-pass CSR8675, which supports Bluetooth 5.0 and high-pass aptX/aptX HD/aptX low delay, AAC, SBC and LDAC audio coding formats. Feiao BTR3K uses two independent AK4377A DACs and amplifiers, which are responsible for left and right channels respectively. Independent double crystal oscillator can also restore audio signals with different sampling rates more.
Another is BTR3K, which uses Vian WP3881 Type-C input overvoltage protection switch with a maximum withstand voltage of 28V to prevent fast charging equipment from damaging the circuit. And the CSR8675 can provide 200mA charging current for the built-in lithium battery without external components. Built-in battery 330mAh, from Shenzhen Xinglengda. CSR8675 also supports Qualcomm cVc 8.0 call noise reduction technology. BTR3K has a silicon wheat that can be used for call functions.
In addition, FiiO Feiao BTR3K is also very rich in usage scenarios. It can connect two Bluetooth devices at the same time, and the volume can be controlled separately. The Type-C interface is adopted to support charging while using, and a computer can also be connected to be used as an external decoder. There are two types of audio output interfaces, which are balanced 2.5mm and 3.5mm, which are relatively simple and convenient for ordinary consumers and can also meet the needs of some.
author:
I love audio network05-23 14:12
website: https://weibo.com/ttarticle/p/show?id=2309404507748120264775
