Abstract: A sensing circuit for an electrochemical sensor includes a digital-to-analog converter (DAC), an operational amplifier, an instrumentation amplifier, and an analog-to-digital converter (ADC). The DAC generates a biased ground voltage signal which is received by the operational amplifier. The operational amplifier creates a high current biased voltage on one of a pair of terminals connected to the electrochemical sensor. The instrumentation amplifier receives a signal from the pair of terminals, and generates an output representative of a voltage across the pair of terminals with reference to the high current biased ground voltage signal. The ADC converter receives the output and derives an actual voltage reading taken by the electrochemical sensor.
Type:
Grant
Filed:
July 22, 2015
Date of Patent:
February 14, 2017
Assignee:
ATLAS SCIENTIFIC LLC
Inventors:
Efrem Press, Jon Lindgren, Jordan Press
Abstract: A driving circuit for a fluid conductivity sensor includes a pulse width modulation unit, an H-bridge, first and second differential amplifiers, and an analog-to-digital converter (ADC). The pulse width modulation unit generates two opposing driving signals. The H-bridge receives the two opposing driving signals and generates two H-bridge outputs. The first differential amplifier includes first inputs connected in parallel to a shunt resistor. One of the first inputs is coupled to the two generated H-bridge outputs. The second differential amplifier includes second inputs connected in parallel with a pair of terminals having a sensor attached thereto. One of the second inputs and the pair of terminals receive a signal from the other of the two generated H-bridge outputs. The ADC receives a first output representative of a first current from the first differential amplifier; and a second output representative of a second current from the second differential amplifier.
Type:
Grant
Filed:
March 17, 2015
Date of Patent:
November 22, 2016
Assignee:
Atlas Scientific LLC
Inventors:
Efrem Press, Jon Lindgren, Jordan Press
Abstract: A multi-stage cryocooler having a relatively low temperature stage to cool to less than about 15K and having a regenerator including a ductile intermetallic compound including one or more rare earth elements and one or more non-rare earth metals.
Type:
Grant
Filed:
February 18, 2005
Date of Patent:
June 23, 2009
Assignee:
Atlas Scientific
Inventors:
Karl A. Gschneidner, Jr., Alexandra O. Tsokol, Vitalij K. Pecharsky