Electrolysis: processes – compositions used therein – and methods – Electrolytic analysis or testing – For ion concentration
Patent
1997-05-02
1999-06-15
Tung, T.
Electrolysis: processes, compositions used therein, and methods
Electrolytic analysis or testing
For ion concentration
204401, 204408, 204416, 2057875, 257253, G01N 27333
Patent
active
059118733
ABSTRACT:
An apparatus for measuring ion concentration of a solution includes an ion sensitive field effect transistor (ISFET), a reference device, an ISFET control circuit, a memory, a measurement circuit and a diagnostic circuit. The ISFET has a drain, a source, an ion sensitive gate region and a plurality of device characteristics. The reference device is separated from the gate region by a sample solution. The ISFET control circuit is coupled to the ISFET and operates the ISFET at a drain-source voltage V.sub.DS and at n successive drain currents I.sub.Di and corresponding gate-source voltages V.sub.GSi, wherein i is an integer from 1 to n and n is an integer greater than 1. The memory stores the plurality of device characteristics and the n successive drain currents I.sub.Di and gate-source voltages V.sub.GSi. The measurement circuit measures ion concentration of the solution as a function of at least one of the n successive drain currents I.sub.Di and gate-source voltages V.sub.GSi and the plurality of device characteristics stored in the memory. The diagnostic circuit measures at least one of the device characteristics of the ISFET as a function of the n successive drain currents I.sub.Di and gate-source voltages V.sub.GSi.
REFERENCES:
patent: 4020830 (1977-05-01), Johnson et al.
patent: 4198851 (1980-04-01), Janata
patent: 4267504 (1981-05-01), Bergveld
patent: 4322680 (1982-03-01), Janata et al.
patent: 4385274 (1983-05-01), Shimada et al.
patent: 4397714 (1983-08-01), Janata et al.
patent: 4411741 (1983-10-01), Janata
patent: 4456522 (1984-06-01), Blackburn
patent: 4488556 (1984-12-01), Ho
patent: 4514263 (1985-04-01), Janata
patent: 4532013 (1985-07-01), Dietz et al.
patent: 4641084 (1987-02-01), Komatsu
patent: 4641249 (1987-02-01), Gion et al.
patent: 4671852 (1987-06-01), Pyke
patent: 4691167 (1987-09-01), Vlekkert et al.
patent: 4701253 (1987-10-01), Ligtenberg et al.
patent: 4798655 (1989-01-01), Diamond
patent: 4879517 (1989-11-01), Connery et al.
patent: 4952300 (1990-08-01), Diamond
patent: 5022980 (1991-06-01), Tanaka et al.
patent: 5319226 (1994-06-01), Sohn et al.
patent: 5431883 (1995-07-01), Barraud
Karl King, "Dual pH Electrode Improves On-Line Diagnostics", pp. 33-37, 1995 ISA Conference, New Orleans, LA (Oct. 1995).
Prof. Dr. Werner Melzer, "Maintenance Free Online pH-Measurement", pp. 57-64, 1995 ISA Conference, New Orleans, LA (Oct. 1995).
Hon-Sum Wong and Marvin E. White, "A CMOS-Integrated "ISFET-Operational Amplifier" Chemical Sensor Employing Differential Sensing", IEEE Transactions on Electron Devices, vol. 36. No. 3, Mar. 1989.
Gray James R.
McCarron Robert Tanner
Rosemount Analytical Inc.
Tung T.
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