TY - GEN
T1 - A NIR CMOS Preamplifier with DC Photocurrent Rejection for Pulsed Light Source
AU - Wong, Alex K. Y.
AU - Pun, Kong-Pang
AU - Zhang, Yuan-Ting
AU - Leung, Ka Nang
PY - 2006/11
Y1 - 2006/11
N2 - A micro-power transimpedance amplifier is presented to acquire modulated optical signal for heart-rate measurement The circuit is composed of a transimpedance amplifier (TIA), a sample-and-hold (S/H) circuit, an error amplifier and a current-sink transistor, configured in a feedback loop to reject DC photocurrent generated from photodiode, which varies from person to person. To reduce power consumption, the LED is pulsed and thus the input to the TIA is a modulated current pulse. The proposed circuit is designed to accurately reject the average of the original continuous time signal, rather than that of the pulsed signal. This is achieved by inserting an S/H stage between the TIA and error amplifier. Simulation results show that the circuit works properly from a 2-V power supply and has a rejection range from 40 μA to 95 μA.
AB - A micro-power transimpedance amplifier is presented to acquire modulated optical signal for heart-rate measurement The circuit is composed of a transimpedance amplifier (TIA), a sample-and-hold (S/H) circuit, an error amplifier and a current-sink transistor, configured in a feedback loop to reject DC photocurrent generated from photodiode, which varies from person to person. To reduce power consumption, the LED is pulsed and thus the input to the TIA is a modulated current pulse. The proposed circuit is designed to accurately reject the average of the original continuous time signal, rather than that of the pulsed signal. This is achieved by inserting an S/H stage between the TIA and error amplifier. Simulation results show that the circuit works properly from a 2-V power supply and has a rejection range from 40 μA to 95 μA.
UR - https://www.scopus.com/pages/publications/52949131523
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-52949131523&origin=recordpage
U2 - 10.1109/BIOCAS.2006.4600295
DO - 10.1109/BIOCAS.2006.4600295
M3 - RGC 32 - Refereed conference paper (with host publication)
SN - 9781424404360
T3 - IEEE Biomedical Circuits and Systems Conference Healthcare Technology
SP - 9
EP - 12
BT - IEEE BiOCAS2006: Biomedical Circuits and Systems Conference
PB - IEEE
T2 - IEEE 2006 Biomedical Circuits and Systems Conference Healthcare Technology (BioCAS 2006)
Y2 - 29 November 2006 through 1 December 2006
ER -