An adaptive-resolution signal-specific ADC for sensor-interface applications
- 78 Downloads
In this paper, a signal-specific analog-to-digital converter (ADC) with a new structure is proposed, in which the resolution of the ADC is adaptively adjusted by the activity of the input neural signal. The main advantages of the proposed technique for converting sparse and burst-like signals include (1) output data-rate reduction, and (2) power savings in ADC and its succeeding blocks. These benefits are obtained owing to the truncation of bits along in-active part of the signal. The extra blocks for realizing the proposed adaptive-variable resolution technique are fully-digital, which add minimum complexity and design overhead to the ADC. The proposed ADC has a suitable data compression capability at the expense of a tolerable degradation in quality of the reconstructed signal. The simulation results in a 180 nm CMOS technology show power savings of up to 39.5% and a compression ratio of 3.9×, as compared to the conventional structure.
KeywordsData compression SAR ADC Signal-dependent behavior Nonlinear quantization Biomedical signal
- 8.Taherzadeh-Sani, M., Lotfi, R., & Nabki, F. (2014). A 10-bit 110 kS/s 1.16 μW SA-ADC with a hybrid differential/single-ended DAC in 180-nm CMOS for multichannel biomedical applications. IEEE Transactions on Circuits and Systems—II: Express Briefs, 61(8), 584–588.Google Scholar
- 10.Lyu, Y.-F., Wu, C.-Y., Liu, L.-C. & Chen, W.-M. (2013). A low power 10 Bit 500 kS/s delta-modulated SAR ADC (DMSAR ADC) for implantable medical devices. In Proceedings of IEEE international symposium on circuits systems, (pp. 2046–2049).Google Scholar
- 11.Rahiminejad, E., Saberi, M., & Lotfi, R. (2016). A power-efficient signal-specific ADC for sensor-interface applications. IEEE Transactions on Circuits and Systems II: Express Briefs.Google Scholar
- 15.Lima Silva, V. M., & Cavalcanti Catunda, S. Y. (2017). Non-uniform sampling based ADC architecture using an adaptive level-crossing technique. In IEEE international instrumentation and measurement technology conference (I2MTC), (pp. 1-6).Google Scholar
- 21.Kumar, A. M., Veeramachaneni, S., & Srinivas, M. B. (2010). Towards realizing variable resolution analog to digital converters. In Asia pacific conference on postgraduate research in microelectronics and electronics (PrimeAsia).Google Scholar
- 26.Kurchuk, M., & Tsividis, Y. (2010). Signal-dependent variable-resolution clockless A/D conversion with application to continuous-time digital signal processing. IEEE Transactions on Circuits and Systems-I: Regular Papers, 57(5).Google Scholar
- 29.MIT-BIH Arrhythmia database. [Online]. http://physionet.org/cgi-bin/atm/ATM.