ADAU1701 is a complete single-chip audio system, including 28/56 bit audio DSP, ADC, DAC and similar microcontroller control interface. Signal processing includes balance, mixing, bass enhancement, multi-band dynamic processing, delay compensation, and stereo image expansion. It can compensate for the limitations of real-world speakers, amplifiers, and listening environments, and dynamically improve the perceived audio quality.
The first circuit we introduce below is to realize analog audio input and class D output through the ADAU1701 SigmaDSP codec, low-power SSM2306 class D amplifier and ADP3336 LDO regulator.
Circuit functions and advantages The circuit shown in Figure 1 connects an ADAU1701 codec with an integrated SigmaDSP® core to the SSM2306 2 W stereo Class-D amplifier and ADP3336 low-dropout regulator. The ADAU1701 has two built-in ADCs and four DACs, so it can process a stereo audio signal and output the separately processed signals to one line-level output and one amplified output at the same time. In this way, the line output and the amplified output can be processed in the SigmaDSP core with different signal processing methods, such as customized EQ, a customized compressor at the chip level for a specific output, or a spatial effect adjusted according to a specific speaker configuration. The ADP3336 generates a 3.3 V power supply for use by the ADAU1701. SSM2306 is a 2 W stereo Class D amplifier with ultra-low idle current and high efficiency. It does not require a large external inductor, but requires very few external components and the system size is small. The power supply voltage of the amplifier is not provided by the regulator, but directly from the 5 V system power supply. The system can provide audio signal processing path output for low-efficiency amplifiers, and is suitable for systems such as radios, multimedia docking stations, or PC speakers.
Circuit description
The DAC output of the ADAU1701 is connected to the SSM2306 through a resistor and capacitor at each input of the amplifier. A 0.10 μF capacitor and a 13.0 kΩ resistor are connected in series and connected between the output of the ADAU1701 and the input of the SSM2306 to implement a 28 Hz high-pass filter. These resistors also set the gain of the amplifier to about 6 dB. The full-scale output of the ADAU1701 is 0.9 V rms, so the SSM2306 amplifies it to a full-scale 1.8 V rms (5.09 V peak-to-peak). When SSM2306's VDD = 5 V, this full-scale value closely matches the clamp level of the amplifier.
This circuit uses a multi-purpose (MP) pin of ADAU1701 to control the active low pin of SSM2306. This connection, coupled with a 10 kΩ pull-up resistor, allows the SigmaDSP program to cleanly disable the Class D amplifier without popping or clicking.
Simply place a ferrite bead and 1.0 nF capacitor on each pin in front of the speaker, and the output of the SSM2306 Class D amplifier will remain stable.
The power supply voltage of SSM2306 can be obtained directly from a 5 V power supply, such as a battery, but the ADAU1701 requires a 3.3 V regulated power supply, which is generated by ADP3336. The output voltage of the ADP3336 is set to 3.3 V through 140 kΩ and 78.7 kΩ feedback resistors. Place a capacitor as low as 1.0 μF between the output pin and ground to keep the regulator output stable. The 1.0 μF capacitor at the input of the regulator is used to decouple the stray inductance between the circuit board and the 5 V power supply. In this circuit, the shutdown pin of the regulator only needs to be connected to the input voltage, so that the IC will be enabled when there is an input voltage.
Common changes
In addition to ADAU1701, this circuit can also be set up with other SigmaDSP processors with integrated DAC, such as ADAU1761. ADAU1702 can also replace ADAU1701, the only difference between the two is the SigmaDSP program and data memory size. Class D amplifiers SSM2301, SSM2302 and SSM2304 are slightly different from the SSM2306 used in this design. The audio inputs of these three amplifiers do not require external resistors to set the gain. SSM2301 is a mono amplifier, not a stereo amplifier.
Digital audio system solution based on ADAU1701 and ARM7
ZGAR FIT
ZGAR electronic cigarette uses high-tech R&D, food grade disposable pod device and high-quality raw material. All package designs are Original IP. Our designer team is from Hong Kong. We have very high requirements for product quality, flavors taste and packaging design. The E-liquid is imported, materials are food grade, and assembly plant is medical-grade dust-free workshops.
From production to packaging, the whole system of tracking, efficient and orderly process, achieving daily efficient output. We pay attention to the details of each process control. The first class dust-free production workshop has passed the GMP food and drug production standard certification, ensuring quality and safety. We choose the products with a traceability system, which can not only effectively track and trace all kinds of data, but also ensure good product quality.
We offer best price, high quality Vape Device, E-Cigarette Vape Pen, Disposable Device Vape,Vape Pen Atomizer, Electronic cigarette to all over the world.
Much Better Vaping Experience!
E-Cigarette Vape Pen,Disposable Device Vape,Vape Pen Atomizer,Latest Disposable E-Cigarette OEM vape pen,OEM electronic cigarette
ZGAR INTERNATIONAL(HK)CO., LIMITED , https://www.szvape-pods.com