ETRI Journal

Electronics and Telecommunications Research Institute (한국전자통신연구원)
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Ultra-Low-Power Differential ISFET/REFET Readout Circuit

  • Received : 2008.11.17
  • Accepted : 2009.02.18
  • Published : 2009.04.30
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Abstract

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.

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References

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