Lab 7 - Practical Signal Conditioning

Practical Signal Conditioning

Objective:

Use a scaling and level-shifting circuit to process the output signal from a temperature sensor to produce temperature reading in Fahrenheit.

Process:

1. Theory
         Scaling is defined as multiplying a current by a constant to change its amplitude while level-shifting is the process of adding a constant to the current.

2. Problem
         Turn room temperature degree reading Celsius into unit reading of Fahrenheit.

3. Given
         Use Semiconductor LM35
         R_1 = 1000 ohms
         V_in = +4 to +20volts

4. Circuit Calculations

Finding R_1 and R_2

Encountered an obstacle during caluculations as we noticed that breadboards only accept input of two voltages and we needed a third for V_ref leading to redesigning of circuit

Final design for Circuit 

5. Built Circuit

6. Data collected and analyzed

Conclusion:

During lab procedure we discovered that we did not have the appropriate equipment to proceed with the experiment and therefore had to alter the original circuit given to accommodate for our third voltage input. Once that was resolved we were able to get a a voltage measurement of the room in Fahrenheit with a 10% error rate meeting, the objective of amplifying the signal from Celsius.