ADAU1701 is a complete single-chip audio system that integrates a 28/56-bit audio DSP, ADC, DAC, and a microcontroller-like control interface. It offers advanced signal processing features such as balance, mixing, bass enhancement, multi-band dynamic processing, delay compensation, and stereo image expansion. This device can compensate for the limitations of real-world speakers, amplifiers, and listening environments, delivering an enhanced audio experience.
The first circuit we present below uses the ADAU1701 SigmaDSP codec to process analog audio input and drive a Class D output through the low-power SSM2306 amplifier and ADP3336 LDO regulator. This design provides a compact and efficient solution for various audio applications.
The circuit shown in Figure 1 connects the ADAU1701, which includes a built-in SigmaDSP core, with the SSM2306 2 W stereo Class-D amplifier and the ADP3336 low-dropout voltage regulator. The ADAU1701 has two ADCs and four DACs, allowing it to process stereo audio signals and provide separate outputs—line-level and amplified. This enables different signal processing techniques, such as custom EQ, chip-level compression, or spatial effects tailored to specific speaker setups. The ADP3336 supplies a stable 3.3 V to the ADAU1701, while the SSM2306 draws power directly from a 5 V supply. With its high efficiency and minimal external components, this design is ideal for applications like radios, multimedia docks, and PC speakers.
The DAC output from the ADAU1701 is connected to the SSM2306 via a resistor and capacitor network, forming a 28 Hz high-pass filter. A 13 kΩ resistor and 0.1 μF capacitor are used to set the gain and shape the frequency response. The full-scale output of the ADAU1701 is 0.9 V RMS, which the SSM2306 amplifies to 1.8 V RMS (5.09 V peak-to-peak) when powered by 5 V. This matches the amplifier's clamp level closely, ensuring optimal performance.
The MP pin of the ADAU1701 is used to control the active-low enable pin of the SSM2306. Combined with a 10 kΩ pull-up resistor, this setup allows the SigmaDSP program to disable the amplifier cleanly without any audible noise.
To stabilize the output of the SSM2306, a ferrite bead and a 1 nF capacitor are placed on each speaker connection. This helps maintain signal integrity and reduce interference.
The SSM2306 is powered directly from a 5 V source, while the ADAU1701 requires a 3.3 V regulated supply provided by the ADP3336. The feedback resistors (140 kΩ and 78.7 kΩ) set the output voltage to 3.3 V, and a 1 μF capacitor between the output and ground ensures stability. An additional 1 μF capacitor at the input decouples stray inductance from the 5 V supply. The shutdown pin of the ADP3336 is tied to the input voltage, enabling the IC automatically when power is applied.
In addition to the ADAU1701, other SigmaDSP processors such as the ADAU1761 can be used in similar configurations. The ADAU1702 is also a suitable alternative, differing mainly in memory size. For Class D amplifiers, the SSM2301, SSM2302, and SSM2304 offer slight variations, including mono support and different input configurations.
This digital audio system solution based on the ADAU1701 and ARM7 processor demonstrates how flexible and powerful SigmaDSP technology can be in modern audio designs.
Refurbished Gaming Laptops,Refurbished Laptops Under $100,Used Gaming Laptops For Sale,Second Hand Gaming Laptop
Guangzhou Panda Electronic Technology Co., LTD , https://www.panda-3c.com