Open AccessUltra‐Low‐Power Differential ISFET/REFET Readout Circuit
Author(s) -
Thanachayat Apinunt,
Sirimasakul Silar
Publication year - 2009
Publication title -
etri journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 46
eISSN - 2233-7326
pISSN - 1225-6463
DOI - 10.4218/etrij.09.0208.0368
Subject(s) - isfet , mosfet , cmos , electrical engineering , field effect transistor , transistor , linearity , materials science , common mode rejection ratio , electronic engineering , optoelectronics , voltage , engineering , operational amplifier , amplifier
A novel ultra‐low‐power readout circuit for a pH‐sensitive ion‐sensitive field‐effect transistor (ISFET) is proposed. It uses an ISFET/reference FET (REFET) differential pair operating in weak‐inversion and a simple current‐mode metal‐oxide semiconductor FET (MOSFET) translinear circuit. Simulation results verify that the circuit operates with excellent common‐mode rejection ability and good linearity for a single pH range from 4 to 10, while only 4 nA is drawn from a single 1 V supply voltage.