Smart Sensor Technology Launched

Alphasense (UK), specialists in gas sensor manufacturer for safety and industrial markets, launches new smart sensor technology for its electro-chemical sensors. The AFE (Analogue Front End) is a programmable device for use in micro power electro-chemical sensing applications. It is intended to be used with the sensor, creating a “smart sensor”. It is designed for three-electrode single gas sensors and for two electrode oxygen sensors. This device provides all of the functionality for detecting changes in gas concentration based on a delta current at the working electrode, and generates an output voltage proportional to the cell current.

Transimpedance gain is user programmable through an I2C compatible interface from 3.4kOhm to 440kOhm making it easy to convert current ranges from 5μA to 650uA full scale. Optimised for micro-power applications, the AFE works over a voltage range of 2.7V to 5.5 V. The cell voltage is user selectable using the on board programmability. A temperature sensor is embedded and it can be power cycled through the interface, the output of this temperature sensor can be read by the user through the ‘Out’ pin. Together with the coefficients stored in the on board EEPROM, this information can be used to compensate for the sensor sensitivity drift over temperature.

Additionally user controlled sensor test will be implemented. The tests the sensor for proper connection (all 3 terminals) as well as proper function.

Depending on configuration, total current consumption for the device can be less than 10μA running, for power savings transimpedance amplifier (TIA) can be turned off and instead a load impedance equivalent to the TIA’s inputs impedance is switched in.

Arthur Burnley, Sales & Marketing Director commented, “We are continually developing new technologies especially with respect to electronics and have been working with Semi-conductor manufacturers to provide Smart Sensor Technology that will ease the development and reduce time to market for OEM’s and system builders by providing a ‘smart’ interface to our electro-chemical sensors. This is a further example of developments making a positive contribution to the protection of life in challenging environments. Supporting our customers is one of our highest priorities and the Alphasense team has many decades of design, Manufacturing and Application experience. We are not only improving our products continuously, but also our internal procedures and processes to ensure we offer the highest possible levels of Customer Support”