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Grace Lab1 1
Jessy Grace
G00170423
Lab 1: Inro to Process Control
Grantham University
8/18/2021
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Grace Lab1 2
Digital Signal Conditioning Lab
Introduction:
Week two lab, digital conditioning, consists of digital to analog conversions using the 1 & 0 digits or
better known as the bits of a word. Better put, signal conditioning is taking the input signal to achieve
data or control a process. The two exercises in this lab will model how this is done.
Equipment/Components:
â€¢ Multimeter
â€¢ General Comparator
â€¢ 3 resistors
â€¢ 3Vpp sine wave
â€¢ Oscilloscope
â€¢ 8-bit VDAC
â€¢ single-pole double-throw switch.
â€¢ Multisim
Procedure:
For part one, complete the comparator design by doing the proper calculations to figure the desired
resistance of the resistors. Use 1.25V as the threshold and once calculated simulate in Multisim to
validate the results. Also, use the 3Vpp for the Vin and plot the wave. Then, for part two, select the 8-bit
VDAC and properly design the circuit with the 12V reference. Calculate the analog output voltage first to
record in data table. Simulate and record the measured voltage in the data table. Record all data of
simulations and include screenshots.
Calculations:
Vref = R1/(R1+R2) X 5
Thererfore
R2 = 3R1
Asumming
R1 = R3 = 1 K â„¦
Then
R2 = 3Kâ„¦
Part 2 calculations
Resolution = 12/ (256 -1) = 47mV
Analog output voltage = Resolution *Volts*N
10
0 0 0 0 0 0 0 1 â†’1/ 2 nâˆ’1 âˆ—12âˆ—1=47mV
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Grace Lab1 3
0 0 0 0 1 0 0 1 â†’1/ 2 nâˆ’1 âˆ—12âˆ—9=423mV
0 0 0 1 0 0 0 0 â†’1/ 2 nâˆ’1 âˆ—12âˆ—16=.752mV
0 0 0 1 1 1 1 1 â†’1 /2 nâˆ’1 âˆ—12âˆ—31=1.45V
0 1 0 1 0 1 0 1 â†’1/ 2 nâˆ’1 âˆ—12âˆ—85=4 V
1 0 0 0 0 0 0 0 â†’1/ 2 nâˆ’1 âˆ—12âˆ—128=6.02V
1 1 1 1 1 1 1 1 â†’1/ 2 nâˆ’1 âˆ—12âˆ—255=12V
Circuit design:
Circuit Design comparator
VDAC Design
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Grace Lab1 4
Execution/Results:
High/Low plot
0 0 0 0 0 0 0 1 Measurment 46.875mV
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Grace Lab1 5
0 0 0 0 1 0 0 1 Measurment 421.875mV
0 0 0 1 0 0 0 0 Measurment 750mv
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Grace Lab1 6
0 0 0 1 1 1 1 1 Measurment 1.443V
0 1 0 1 0 1 0 1 Measurment 3.984V
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Grace Lab1 7
1 0 0 0 0 0 0 0 Measurment 6V
1 1 1 1 1 1 1 1 Measurment 11.953V
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Grace Lab1 8
Analysis:
Digital Inputs
Calculated Analog Output
Voltage
Measured Analog Output
Voltage
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 1
47mV
46.875mV
0 0 0 0 1 0 0 1
423mV
421.875mV
0 0 0 1 0 0 0 0
752mV
750mV</