SEMICONDUCTOR INTEGRATED CIRCUITS

A low power low noise analog front end for portable healthcare system

Yanchao Wang, Keren Ke, Wenhui Qin, Yajie Qin, Ting Yi and Zhiliang Hong

+ Author Affiliations

 Corresponding author: Wang Yanchao, wangyanchao@fudan.edu.cn; Yi Ting, yiting@fudan.edu.cn

PDF

Abstract: The presented analog front end (AFE) used to process human bio-signals consists of chopping instrument amplifier (IA), chopping spikes filter and programmable gain and bandwidth amplifier.The capacitorcoupling input of AFE can reject the DC electrode offset.The power consumption of current-feedback based IA is reduced by adopting capacitor divider in the input and feedback network.Besides, IA's input thermal noise is decreased by utilizing complementary CMOS input pairs which can offer higher transconductance.Fabricated in Global Foundry 0.35 μm CMOS technology, the chip consumes 3.96 μA from 3.3 V supply.The measured input noise is 0.85 μVrms (0.5-100 Hz) and the achieved noise efficient factor is 6.48.

Key words: AFEchopping IAlow power consumptionlow noiseNEF



[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
Fig. 1.  System block diagram of AFE.

Fig. 2.  System diagram of IA.

Fig. 3.  Main schematic of IA.

Fig. 4.  Realization of $C$. (a) Structure of tunable capacitor $C_{\rm t}$. (b) Implementation of $C_0.$

Fig. 5.  Relationship of $C_0$ and $V_{\rm c}$.

Fig. 6.  Input impedance model of IA.

Fig. 7.  Schematic of RRL.

Fig. 8.  AC response of RRL.

Fig. 9.  Noise model of AFE.

Fig. 10.  CSF and the control signals.

Fig. 11.  The topology of PGA.

Fig. 12.  CSF and the control signals.

Fig. 13.  Transient response of AFE.

Fig. 14.  (Color online) Measured results of AFE's AC response.

Fig. 15.  Measured input noise density spectrum.

Table 1.   Performance summary and comparison.

Parameter Reference [10] Reference [13] Reference [14] Reference [15] This work
Technology 0.13 $\mu$m 0.5 $\mu$m 0.18 $\mu$m 0.18 $\mu$m 0.35 $\mu$m
Power supply (V) 1 3.3 1.8 1.8 3.3
Supply current ($\mu $A) 12.1 20 11 12.5 3.96
Input impedance (M$\upOmega )$ 4 @ 1 kHz >100 >2000 2000 300 @ 80 Hz
Input noise ($\mu $Vrms) 2.2 - 0.8 0.8 0.85
(20-10 kHz)(0.5-100 Hz)(0.5-100 Hz)(0.5-100 Hz)
DEO (mV) Rail to rail 50 Rail to rail Rail to rail Rail to rail
CMRR (dB) 80 120 82 82 115
PSRR (dB) $>80$ $>80$ - - 100
NEF 4.9 9.2 12 16 6.48
Gain (dB) 40 52-68 10-40 43-63 41-79
DownLoad: CSV
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
  • Search

    Advanced Search >>

    GET CITATION

    shu

    Export: BibTex EndNote

    Article Metrics

    Article views: 2632 Times PDF downloads: 20 Times Cited by: 0 Times

    History

    Received: 06 March 2015 Revised: Online: Published: 01 October 2015

    Catalog

      Email This Article

      User name:
      Email:*请输入正确邮箱
      Code:*验证码错误
      Yanchao Wang, Keren Ke, Wenhui Qin, Yajie Qin, Ting Yi, Zhiliang Hong. A low power low noise analog front end for portable healthcare system[J]. Journal of Semiconductors, 2015, 36(10): 105008. doi: 10.1088/1674-4926/36/10/105008 Y C Wang, K R Ke, W H Qin, Y J Qin, T Yi, Z L Hong. A low power low noise analog front end for portable healthcare system[J]. J. Semicond., 2015, 36(10): 105008. doi: 10.1088/1674-4926/36/10/105008.Export: BibTex EndNote
      Citation:
      Yanchao Wang, Keren Ke, Wenhui Qin, Yajie Qin, Ting Yi, Zhiliang Hong. A low power low noise analog front end for portable healthcare system[J]. Journal of Semiconductors, 2015, 36(10): 105008. doi: 10.1088/1674-4926/36/10/105008

      Y C Wang, K R Ke, W H Qin, Y J Qin, T Yi, Z L Hong. A low power low noise analog front end for portable healthcare system[J]. J. Semicond., 2015, 36(10): 105008. doi: 10.1088/1674-4926/36/10/105008.
      Export: BibTex EndNote

      A low power low noise analog front end for portable healthcare system

      doi: 10.1088/1674-4926/36/10/105008
      Funds:

      Project supported by the Science and Technology Commission of Shanghai Municipality (No.13511501100), the State Key Laboratory Project of China (No.11MS002), and the State Key Laboratory of ASIC & System, Fudan University.

      More Information

      Catalog

        /

        DownLoad:  Full-Size Img  PowerPoint
        Return
        Return