In a single-ended input system, the input is a high-pass filter, and the input capacitance Ci is an essential component. The design of this high-pass filter is directly related to the performance of the amplifier, especially the performance of its lower frequency. The parameter selection of input resistance and input capacitance is crucial because they directly affect the cut-off frequency of the filter.

    When the input frequency of the signal is in the audio range, the accuracy requirements for the input capacitance Ci are relatively loose, generally ± 10% or higher. This is because the mismatch of capacitance values can have an impact on the performance of the filter, which in turn affects the overall audio performance. However, while the input capacitance Ci is too large, it may increase the low frequency response, but it also increases the cost and footprint. For those application scenarios that have strict requirements for cost and size, excessive input capacitance is obviously unfavorable.

    ChipSourceTek-CST8110 is a high performance audio power amplifier, and the choice of decoupling capacitor Cs is equally important. In the application of amplifier, the power bypass design is particularly critical, which affects not only the noise performance, but also the voltage ripple suppression performance of the power supply. The ChipSourceTek-CST8110 requires proper power decoupling to ensure high efficiency and low harmonic distortion. Decoupling capacitors usually use low-impedance ceramic capacitors and are placed as close as possible to the chip power supply pin to reduce the impact of resistance, capacitance and inductance in the circuit on the power conversion efficiency. A typical configuration is a 220uF electrolytic capacitor in parallel with a 1uF ceramic capacitor. Capacitors are obviously disadvantageous.

    The ChipSourceTek-CST8110 has an internal two-stage amplification structure, the first stage gain can be configured with an external resistor, while the second stage gain is internally fixed. For fully differential applications, the gain of the amplifier can be configured by selecting the parameter value of the input resistance Ri, while for single-ended applications, the gain is halved. The balance between output and feedback depends on the impedance match of the circuit, and the elimination of CMRR (common mode rejection ratio), PSRR (power supply rejection ratio) and second harmonic distortion can be optimized. Therefore, the effect of optimization with a precision of 1% resistance is more significant.

    In the PCB layout, the input resistance should be as close as possible to the input pin of the chip to obtain a better signal-to-noise ratio effect and a higher input impedance. The configuration of low gain and high voltage signal can make the performance of the chip more outstanding.

    In addition to system cost and size, noise performance is also an important consideration. The size of the input coupling capacitance affects the noise performance. A large input coupling capacitance requires more charge to reach the static DC voltage (usually the midpoint voltage of the power supply, i.e. 1/2VDD). These charges come from the output of the feedback, which often produces noise when the device is enabled. Thus, minimizing the input capacitance based on the required low-frequency response minimizes the on-off noise.

    The ChipSourceTek-CST8110 has been designed with a variety of performance metrics in mind, including noise performance, power supply voltage ripple suppression, gain stability, and signal-to-noise ratio. Through careful selection of input capacitors Ci and decoupling capacitors Cs, as well as precise configuration of input resistance Ri, high performance of the system can be achieved. In addition, the ChipSourceTek-CST8110 also has overtemperature protection to ensure the safety of the circuit when the temperature is too high.

    The ChipSourceTek-CST8110 excels in audio power amplifier applications, and its well-designed internal structure and flexible configuration options make it ideal for high performance audio systems. Whether in portable devices or other volume - and cost-sensitive applications, the ChipSourceTek-CST8110 delivers consistent and reliable performance.