PC/CP300 Electronics Laboratory II

Resistive Sensors Prelab Requirements

You will be using the following resistive sensors:

Thermistor

• Image of in-stock thermistors:
  • on left --> Thermistor PTC 12V 1 OHM 120C [datasheet, PTC Application Notes];
  • on right --> Disc Type NTC Thermistors 20 Ohm [datasheet, NTC Application Notes];

1. What form of energy does the device transform and what form of output does it produce?
2. Give a brief description of how the sensor works and how it could be used in a circuit.
3. What does the PTC/NTC notation on a thermistor mean?
4. You will have to calibrate the sensor in the lab. For the calibration, you will have to vary the input to the sensor and measure the resulting output. Develop one or two plans with your partner for how you will obtain a range of input values to the sensor.
   

Light dependent resistor (LDR), photocell, photoresistor, photoconductive cell

• Image of in-stock photoresistors
  • on left --> hermetic (CdS photoconductive cell in a flat lens package)
  • centre and right --> regular open cell
• Choosing the Detector for your Unique Light Sensing Application

1. What form of energy does the device transform and what form of output does it produce?
2. Give a brief description of how the sensor works and how it could be used in a circuit.
3. You will have to calibrate the sensor in the lab. For the calibration, you will have to vary the input to the sensor and measure the resulting output. Develop one or two plans with your partner for how you will obtain a range of input values to the sensor.