case study # 04

High-Performance Audio


Kapik has a history of leadership in innovation. Our experience in mixed signal technology for audio led us to independently develop a significant patent relating to Digital Acoustic Noise Reduction (DANR). The strength of the patent also enabled Kapik to propose a highly integrated and ultra low-power DANR system to a tier-one Asian consumer electronics company.

The specifications of the design, which were based on applications in earbud-style headphones and hearing aids, were highly aggressive. In fact the customer believed that they were unobtainable, given the state-of-the-art technology of the time. However, a successful 65nm silicon demonstrator of several key components of the design -- including an ultra-low power ADC -- ultimately proved Kapik’s ability to engineer highly innovative, viable technology.

The key specifications for the development were as follows:

  • Aggressive, ultra low-power requirements: Our goal was to exceed typical industry standards while ensuring that the system was robust enough to work over the large process variations found in the 65nm CMOS.
  • Interoperability with different portable electronics: The technology would need to be compatible with other portable systems by the device maker and other OEMs.

The key outcomes of the development were:

  • A state-of-the-art, low-power ADC: To achieve a very low power level and enable integration with other portable electronics, we developed an ADC that significantly improved on existing Delta-Sigma architectures.
  • Implemented in digital an optimized low latency DANR filter and developed a supporting software platform: The digital filter optimized area and minimized power while satisfying the tight latency requirements of the DSP. A software module to generate appropriate coefficients for the DANR filter was also created to enable easy development of filters suitable for different headphones and filter responses.
  • Several IP building blocks in 65nm: Kapik development several power management and signal conditioning blocks (e.g.: charge pumps, LDOs, POR) which operated with a low supply voltage (<0.9V) while achieving robust performance.

Ultimately our clients were impressed with our results. We were able to prove challenging power requirements and raised the bar on how mixed signal technologies can be used to address noise reduction. We were also able to make a key advancement in compressing the signal processing pipeline, which enabled the reuse of several processing blocks for various purposes and kept area and leakage power dissipation down.

Interested in finding out more about our IPs and expertise in mixed signal and smart analog design for audio or learning about how we can help you? Contact us today.

Tags: power, consumer, medical, audio, IP, ADC