4bit TTL input

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D/A Converter

• 4-bit TTL input
• 1 volt output resolution

Justin Griffin Mahmood Subhani Ross Aten
2
Project Requirements

• What is a D/A Converter?
• What does TTL mean?
• What does the 1 volt output resolution mean?

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Binary Weighted

• http//www.electronicproducts.com/ShowPage.asp?SEC
  TION3700PRIMIDFileNamesepana1.sep2003

4
R-2r Ladder
Rf 32k R 10k Vref 5v
(Rf/R) Vref 15
http//hyperphysics.phy-astr.gsu.edu/hbase/electro
nic/dac.html
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R-2r Ladder
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V1
V2
V3
V4
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Output Voltage
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Op Amp
http//www.st-andrews.ac.uk/www_pa/Scots_Guide/da
tasheets/Opamps/741.html
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R-2R Ladder DAC
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(No Transcript)
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Alternate Ladder
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Results from the First Design
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Results from the First Design
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R-2R Ladder DAC (using Elvis Digital Input)
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Results Using Digital Input from Elvis
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Results Using Digital Input from Elvis
Average Error Without Grounded Zeros 20.5235
Average Error With Grounded Zeros 0.2737
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Scaled Oscilloscope Output
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Stand Alone Oscilloscope
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Stand Alone Oscilloscope
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Analysis
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Analysis
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Analysis
1.875V
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Analysis
2V
1.875V
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Final R-2R Ladder DAC
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Switch
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Final Scaled Oscilloscope Output
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Final Stand Alone Oscilloscope Output
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Final Stand Alone Oscilloscope Output
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Temperature Analysis For R-2R Ladder
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Temperature Analysis For R-2R Ladder
Average Error Due to Heat 5.1036
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Temperature Analysis For Binary-Weighted
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Temperature Analysis For Binary-Weighted
Average Error Due to Heat 3.6031
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Gantt Chart
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Budget
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Budget
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Resources

• http//w1.859.telia.com/u85920178/begin/opamp00.h
  tm
• http//hyperphysics.phy-astr.gsu.edu/hbase/electro
  nic/dac.html
• http//www.st-andrews.ac.uk/www_pa/Scots_Guide/da
  tasheets/Opamps/741.html
• http//www.engr.sjsu.edu/ee124/p-intro.html
• http//w1.859.telia.com/u85920178/begin/opamp00.h
  tm