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Biosensing Biosensing is sensing and transmitting information about a biological process of an individual under observation. Two common technologies used are: Bio-potential biosensing - most commonly used when information is desired about living tissue - such as heart, brain, and muscle activity; and Optical biosensing - most commonly used in pulse oximetry (SP02) applications and optical-based heart rate monitors. Chemical pH sensing is used to monitor water quality by measuring the concentration of hydrogen ions in a solution. The various ways to sense these items are chemical sensing: highly integrated, low-power analog front ends (AFE) for pH sensors; optical: specialized spectral filtering can be combined with a light sensor to measure unique transmission/absorption signatures of some chemicals and materials; intelligent wavelength sensing: DLP® technology provides intelligent, programmable wavelength selection filter eliminating the need for expensive array detectors, resulting in high performance at lower price points with a small form factor. Current/Power Current measurement is aimed at understanding the consumption by a load, whether the entire system or individual voltage rails. In addition to measuring the current, many systems want to understand the supply voltage rails along with the current to calculate the overall system power consumption. Flow Many end use equipment in a number of markets need to accurately measure the flow of fluid, heat, and gases for metering or process control applications. Whether it is a water meter for a residential or industrial utility, gas meter or process control meter for heating and cooling of critical systems, the flow must be accurately measured for proper billing and system control. These systems often are in remote locations with monitoring powered by a battery source and require a low-power and highly accurate sensing technology. Gas/Fluid Gas-sensing applications detect the quantity and level of gas in the environment, including toxic gases, oxygen, carbon dioxide, methane, and carbon monoxide. Air quality in health and safety applications are becoming an important factor especially in the building automation and automotive markets. Humidity Humidity sensors determine the amount of water vapor / moisture in the air. Because relative humidity is a function of temperature, humidity sensors also usually include integrated temperature sensors. Level Many products in many markets make use of water, oil, fuel, and other fluids. Whether it is water in a coffee maker, fuel in an automotive tank, or chemicals in a factory process, the performance and lifetime of these systems rely on knowing the level of fluid present at any time. Because different systems have different requirements for accuracy, cost, reliability, and sensor location, there are several technologies to address the level sensing application. Light Optical sensing is the conversion of light rays into electronic signals. Often the intensity of light or changes between one or more light beams is being measured. In its simplest form, sensing light intensity is used for lighting controls in everything from tablets/phones to building automation and street lighting. Optical sensing is used in broad range of applications. By monitoring spectrum, phase, geometry, or timing, optical sensing enables advanced applications such as chemical analysis, 3D mapping, medical scanning, and pulse oximetry. Material Material composition sensing/detection is used to uniquely determine the type, amount, or size of conductors, non-conductors, liquids, and other materials. The various ways to sense with material composition are inductive sensing: for conductive materials; capacitive sensing: offers high sensitivity with a low-cost, low-power and highly flexible system design; optical: programmable spectral filtering to measure unique transmission/absorption signatures of some chemicals and materials; and ultrasonic sensing: non-intrusive sensors are simple to design, no maintenance or contact with corrosive materials. Occupancy Occupancy detection is the ability to determine the presence of an object or person. Sensing the physical presence allows for decisions and actions to be made including conserving power through automatically controlling lights, increasing safety by enabling passenger airbags, or increasing responsiveness during an emergency by knowing building occupancy. The various ways to sense are optical sensing: 3D time of flight (ToF) solutions offer the ability to create an accurate 3D map of an environment with minimal latency and excellent accuracy; temperature sensors: Passive infrared sensors are used to detect a change in the heat signature of the area of interest; and ultrasonic sensing: Ideal for line-of-sight measurements to determine the closest object or for intrusion detection. Position Position/Motion sensing is used to determine the location and lateral/linear, rotational, or axial motion of any moving object or component in a system. The various ways to sense are current shunt monitors: used for closed loop control to monitor the current flow into a solenoid for valve control or through a motor; hall effect sensor: low-power and low-cost solution to sense magnetic field generated by a magnet on the target object; inductive sensing: provides sub-micron resolution while being insensitive to environmental contaminants; optical sensing: optical 3D time of flight (ToF) delivers high sensitivity and motion tracking capabilities to enable precise finger, hand, and body tracking; and ultrasonic sensing: achieves long distance range with high immunity to dusty environment. Pressure Pressure sensors are used to measure the pressure of gases and liquids. Pressure measurements typically are made as either absolute: to measure a pressure relative to a vacuum; gauge: to measure a pressure relative to atmospheric pressure; or differential (or relative); to measure pressure difference between two inputs. The various ways to sense in pressure sensing are with high-precision, programmable sensor signal conditioners for accurate pressure measurements. Proximity Proximity sensing is used in applications that either measure the distance of a target object or simply detect its presence. The various was to sense in proximity sensing are capacitive sensing: offers high sensitivity with a low-cost, low-power and highly flexible system design; hall effect sensors: low-power and low-cost solution to sense magnetic field generated by a magnet on the target object; inductive sensing: provides sub-micron resolution while being insensitive to environmental contaminants; and ultrasonic sensing: achieves long distance range with high immunity to dusty environment. Temperature Temperature sensors leverage the highly predictable and linear properties of a silicon PN junction to derive the temperature. Temperature sensors can guarantee high accuracy while requiring zero calibration in the end system. Temperature sensors offer a wide range of integration and multi-channel options to monitor external PN junctions such as diodes, transistors, processors, ASICs, and FPGAs. |
