ESS9038 + CSR8675 Bluetooth fever decoder board supports APTX-HD / LDAC 5.0 reception | Электроника

ESS9038 + CSR8675 Bluetooth fever decoder board supports APTX-HD / LDAC 5.0 reception | Электроника

ESS9038 + CSR8675 Bluetooth fever decoder board supports APTX-HD / LDAC Bluetooth 5.0 reception

Audiophile Bluetooth receiver board Bluetooth supports LDAC / APTX-HD / APTX- -LL / APTX / SBC / AAC protocol JC-LDAC875 audiophile grade Bluetooth audio receiving board adopts CSR8675 chip solution for Bluetooth digital audio signal reception, and transmits SPDIF coaxial digital signal to ESS9038Q2M chip for decoding. The output analog audio signal is amplified and output by 3 dual op amp filters. The LDAC875 module supports wireless Bluetooth reception and one-way AUX analog audio input for switching output. The lossless switching of the relay will not affect the sound quality. The module defaults to the AUX line mode, the switching method is automatic switching, Bluetooth priority. The company's LDAC875 module is a high-level version that supports LDAC / APTX-HD / APTX-LL / APTX / SBC / AAC protocols, and supports a maximum sampling rate of 24bit / 96khz, far exceeding the 24bit / 48knz sampling rate of APTX-HD . LDAC875 is powered by a single DC power supply, and can be used in a wide voltage range of DC 10V-32V. The product has designed an isolated power supply voltage regulator module, which can directly share the power supply in the original power amplifier or the pre-stage equipment, and no longer need independent power supply. It can also be used for car modification. The board comes with an isolated power supply voltage regulator module, which can be directly connected to the 12V power supply on the car. Multi-level voltage regulator design, Bluetooth module, DAC chip, op amp chip are all independent power management chip power supply, op amp uses dual (positive and negative) 14V power supply, absolute fever level design. ①. DC power input interface, red (EXACC) is positive, black (GND) is negative. Support DC10V-32V, Note: AC power supply cannot be used. ②. AUX analog audio input interface, white line (INL) is the left channel, black (GND) is the audio ground line, and red (INR) is the right channel. Note: The audio ground wire cannot be connected wrongly. ③. Audio output interface, white line (L-OUT) is the left channel, black (GND) is the audio ground line, and red (R-OUT) is the right channel. Note: The audio ground wire cannot be connected wrongly. ④. Bluetooth external antenna buckle, the antenna with buckle can be directly buckled, you can use 2.4G antenna. When the module is installed in a metal shell chassis, an external antenna must be added, otherwise the receiving distance will be seriously affected.

Design circuit and material analysis diagram

①CSR8675 Bluetooth solution, support LDAC / APTX-HD / APTX-LL / APTX / SBC / AAC protocol, LDAC supports 24bit / 96khz sampling rate. ② ESS9038Q2M decoder chip, high parameter and high resolution DAC, support up to 32bit / 384khz ③ 3 0PA2604AU operational amplifier filter outputs, 2 near the DAC decoding chip are left and right channel I / V filtering, one chip is responsible for one channel, the separation is better. The latter one is the left and right channel amplification output, which improves the dynamic and thrust. The power conversion circuit converts the input single power supply into a dual (positive and negative) 14V regulated DC power supply to power the op amp. The dual power supply is far better than the single power supply operational amplifier dynamics and sound quality. The output DC of the single-power supply op amp needs to add a coupling capacitor to isolate the DC output. The output of the dual power supply op amp has no DC and does not require the isolation of the coupling capacitor. The sound quality of the direct output is much better than that of the output of the coupling capacitor. ⑤NEC imported relay is responsible for switching between Bluetooth and AUX signals. Automatic detection switching, default AUX, Bluetooth priority. ⑥MCU chip, cooperate with our independently developed firmware program to open the intelligent operation of the control board. ⑦This four-pin is the programming software interface for programming the driver of the Bluetooth motherboard. Motherboard design, fully isolated power module, completely separated from the motherboard design, the power processing circuit will generate some high-frequency magnetic fields, easily interfere with the audio signal, the mother board design is to provide a more pure power environment for the motherboard

Shipping list:

1. LDAC875 motherboard x 1 2. Bluetooth antenna cable x 1 (length about 300mm) 3. Bluetooth receiving antenna x 1 4. 3P audio cable x 1 (length about 200mm) 5. 2P power cable x 1 (length about 200mm)