
SCA is a multi-sensor microsystem (MSM) to monitor for the presence of toxic chemicals (TICs), pollutants, volatile organic compounds (VOCs) and flammable gases in air.
At the core of SCA there is SENSIPLUS, the Sensichips microsensor platform that can interrogate on-chip and off-chip sensors with its versatile and accurate Electrical Impedance Spectrometer (EIS). Analytics performed with EIS allow to exploit chemisorption or ReDox dynamics of the sensitive film to aid gas discrimination. Alternate Current (AC) readout is less sensitive to drifts plus EIS allows to derive an R/C equivalent circuit of the sensor to decouple components that drift from the ones that represent the response to the gas, in support of drift mitigation algorithms. Thanks to its versatile analytical instruments and availability of on-board Interdigitated Electrodes, SCA is also an excellent experimental board for new sensitive materials. Several SCAs can be installed onto long cables for large area continuous monitoring.
Specifications
ELECTRICAL |
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Supply Voltage | 1.5-3.6V |
Max Current | 0.4mA continuous when reading on-chip sensors with EIS |
Size | 8.6×7.8mm |
Interface | I2C or SENSIBUS, single data wire multidrop sensor array cable interface, 1.5-3.6V |
Unique Identifier | OTP 48bits Unique Device Identifier, 16bits User Defined |
ELECTRICAL IMPEDANCE SPECTROSCOPY |
|
Frequency | 3.1mHz to 1.2MHz |
Vpp output sinewave | 156mV to 2.8Vpp |
Coherent demodulation | 1st, 2nd or 3rd harmonic |
Output | Reciprocal of real or imagery component |
Wide Measurement Range | From ohms to 100MΩ |
TEMPERATURE |
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Range | -40°C to 125°C |
Accuracy | ±0.1°C |
POLYMMIDE |
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Detects | Humidity, Vapors |
Range | 0% to 100% |
Accuracy | ±0.1% |
ALUMINUM OXIDE |
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Detects | Ammonium, Humidity |
Limit of detection | 500ppb Ammonium |
PRISTINE GREPHENE |
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Detects | NO2, Oxidants |
Limit of detection | 10ppb NO2 |
HEATED TIN OXIDE |
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Detects | Air contaminants, Flammables, Cigarette smoke |
Limit of detection | 1ppm H2 |
Measurements
Applications
Indoor air quality monitors
Air cleaners
Ventilation control
Hazards monitor

Cables equipped with SCA arrays allow large area monitoring of gases, and estimation of gas cloud propagation direction, velocity and concentration.