This paper describes a current mode A/D converter designed for a maximum input current range of 5nA and a resolution of the order of 1pA. The converter is designed for a potentiostat for amperometric chemical sensors and provides a constant polarization voltage for the measuring electrode. A prototype chip using the dual slope conversion method has been fabricated in a 0.7micron CMOS process. Experimental results from this converter are reported. Design problems and limitations of the converter are discussed and a new conversion technique providing a larger dynamic range and easy calibration is proposed.
|Title of host publication||Proc. 17th NORCHIP Conference|
|Place of Publication||Copenhagen|
|Publication status||Published - 1999|
|Event||17th NORCHIP Conference - Oslo|
Duration: 1 Jan 1999 → …
|Conference||17th NORCHIP Conference|
|Period||01/01/1999 → …|