Sensors are electrical components that are used to measure other physical quantities (temperature, strain, flow, etc.) and produce signals - usually voltage signals - that can be used to determine values for the physical quantity.

• Why learn about sensors?
• Electrical engineers need to know about sensors because they produce electrical signals.  Those signals need to be converted to digital format.  Those signals can be noisy and present a need for filter circuits, etc.  EEs are often called upon in the design and application of sensors.
• Mechanical, civil, chemical and bio engineers encounter sensors when they make measurements (temperature and other quantities).  They need to know about them in order to select appropriate sensors to make measurements of many different physical quantities.
• What should you know to learn about sensors?
• If necessary, review the material about voltage and voltage signals.
• What do you need to know about sensors?
• You need to know basic information about sensors - what they are and how they work.  Sensors we discuss in these lessons include the following:
• Temperature sensors
• Thermocouples
• Thermistors
• LM35 Integrated Circuit Sensors
• Strain Gages
• Flow Sensors
• There will be times that you need to know how to predict dynamic response of sensors, so you will need to know about time-constants.
• How do you use sensors?
• You use sensors to measure physical quantities.  Do some of the lab problems to see how you use sensors.
• What if you need more information?
• There are links within lessons for individual sensors when we could find appropriate material.  Here are some interesting links.
• Practical Temperature Measurements - A classic reference on temperature measurement from Hewlett Packard.  It covers many different ways to measure temperature.
• A data sheet for the LM35.
• A data sheet for thermistors - with additional info on thermocouples.
• Problems
• Click here for Problems on Sensors.

        Here are some links to experiments you can do that will help you learn about sensors.

• An Introduction To Temperature Sensors
• Temperature Sensor Dynamics - Getting Data
• Temperature Sensor Dynamics - Calculating the Time Constants from Data
• A Thermistor Bridge