Title :
Low-noise transimpedance amplifier dedicated to biomedical devices: Near infrared spectroscopy system
Author :
Chaddad, Ahmad ; Tanougast, Camel
Author_Institution :
Dept. of Diagnostic Radiol., Univ. of Texas, Houston, TX, USA
Abstract :
This paper concerns the design and the implementation of a transimpedance amplifier (TIA) dedicated to detector of Near Infrared spectroscopy (NIRS). To reduce the effect of the input capacitance on the bandwidth, a bias circuit with low input impedance is connected to input stage. A single ended common source common gate input stage based on a cascode structure is used to get a higher gain bandwidth closed loop transimpedance amplifier. In addition, a higher open loop gain is got by adding second active load. To increase noise circuit performance, a feedback single transistor technique is considered. The TIA is implemented in 0.18 μm CMOS process. Simulation results show a transimpedance gain of 104.2 dBΩ, -3dB bandwidth of 19 MHz and an equivalent input noise current spectral density of 446 fA/√Hz. A comparative study confirms the feasibility of our proposal.
Keywords :
CMOS integrated circuits; biomedical equipment; capacitance; infrared spectra; operational amplifiers; CMOS process; NIRS; TIA design; TIA implementation; active load; bias circuit; biomedical devices; cascode structure; feedback single transistor technique; gain bandwidth closed loop transimpedance amplifier; input capacitance reduction; input noise current spectral density; low-input impedance; low-noise transimpedance amplifier; near infrared spectroscopy system; noise circuit performance; open loop gain; single-ended common source common gate input stage; transimpedance gain; Capacitors; Gain; Logic gates; Noise; Resistors; Topology; Transistors; CMOS; NIRS; Transimpedance;
Conference_Titel :
Control, Decision and Information Technologies (CoDIT), 2014 International Conference on
Conference_Location :
Metz
DOI :
10.1109/CoDIT.2014.6996963
