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university:courses:electronics:electronics-lab-11m [24 Jul 2017 15:28]
amiclaus change amplitude value to peak-peak
university:courses:electronics:electronics-lab-11m [25 Aug 2017 11:05]
amiclaus add breadboard circuits + xy plots
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 ===== Hardware Setup: ===== ===== Hardware Setup: =====
  
-The waveform generator should be configured for a 1 KHz Sine wave with 4 volt amplitude and 0 offset. The Single ended input of scope channel 2 (2+) is used to measure the voltage at the source. The Scope configured with channel 1+ connected to display the AWG generator output. When measuring the input to output error, channel 2 of the scope should be connected to display 2+ and 2differential.+{{:​university:​courses:​electronics:​mos_src_flw-bb.png|}}
  
 +<WRAP centeralign>​ Figure 2 Source Follower Breadboard Circuit </​WRAP>​
  
- +The waveform generator should be configured for a 1 KHz Sine wave with 4 volt amplitude and 0 offset. The Single ended input of scope channel ​(2+) is used to measure the voltage at the source. The Scope configured with channel 1+ connected to display the AWG generator ​output. When measuring the input to output error, channel 2 of the scope should be connected to display 2+ and 2- differential.
-<WRAP centeralign>​ Figure ​Input, ​output ​waveforms </​WRAP>​+
  
 ===== Procedure: ===== ===== Procedure: =====
 +
 +{{:​university:​courses:​electronics:​mos_src_flw-wav.png|}}
 +
 +<WRAP centeralign>​ Figure 3 Input, output waveforms </​WRAP>​
  
 The incremental Gain (Vout /Vin) of the source follower should ideally be 1 but will always be slightly less than 1. The gain is generally given by the following equation: The incremental Gain (Vout /Vin) of the source follower should ideally be 1 but will always be slightly less than 1. The gain is generally given by the following equation:
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 {{ :​university:​courses:​electronics:​a11m_f2.png?​500 |}} {{ :​university:​courses:​electronics:​a11m_f2.png?​500 |}}
  
-<WRAP centeralign>​ Figure ​Improved Source Follower </​WRAP>​+<WRAP centeralign>​ Figure ​Improved Source Follower </​WRAP>​
  
 +===== Hardware Setup: =====
 +
 +{{:​university:​courses:​electronics:​imp_mos_src_flw-bb.png|}}
 +
 +<WRAP centeralign>​ Figure 5 Improved Source Follower Breadboard Circuit </​WRAP>​
 +
 +===== Procedure: =====
 +
 +{{:​university:​courses:​electronics:​imp_mos_src_flw-wav.png|}}
  
-<WRAP centeralign>​ Figure ​4 Input vs output error for resistor and current source load </​WRAP>​+<WRAP centeralign>​ Figure ​6 Improved Source Follower Waveform ​</​WRAP>​
  
 ====== Source follower output impedance====== ====== Source follower output impedance======
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 {{ :​university:​courses:​electronics:​a11m_f3.png?​500 |}} {{ :​university:​courses:​electronics:​a11m_f3.png?​500 |}}
  
-<WRAP centeralign>​ Figure ​Output impedance test </​WRAP>​+<WRAP centeralign>​ Figure ​Output impedance test </​WRAP>​
  
 ===== Hardware Setup: ===== ===== Hardware Setup: =====
 +
 +{{:​university:​courses:​electronics:​mos_out_imp_test-bb.png|}}
 +
 +<WRAP centeralign>​ Figure 8 Output Impedance Test Breadboard Circuit </​WRAP>​
  
 The waveform generator should be configured for a 1 KHz Sine wave with 2 volt amplitude with the offset set equal to minus the V<​sub>​GS</​sub>​ of M<​sub>​1</​sub>​ ( approximately -V ). This injects a +/- 0.1mA (1V/10KΩ) current into M<​sub>​1</​sub>'​s source. Scope input 2+ measures the change in voltage seen at the source. The waveform generator should be configured for a 1 KHz Sine wave with 2 volt amplitude with the offset set equal to minus the V<​sub>​GS</​sub>​ of M<​sub>​1</​sub>​ ( approximately -V ). This injects a +/- 0.1mA (1V/10KΩ) current into M<​sub>​1</​sub>'​s source. Scope input 2+ measures the change in voltage seen at the source.
  
 ===== Procedure: ===== ===== Procedure: =====
 +
 +{{:​university:​courses:​electronics:​mos_out_imp_test-wav.png|}}
 +
 +<WRAP centeralign>​ Figure 9 Output Impedance Test Waveform </​WRAP>​
  
 Plot the measured voltage amplitude seen at the source. The nominal source current in M<​sub>​1</​sub>​ is (Vn - V<​sub>​GS</​sub>​) / 4.7KΩ or 720uA. We can calculate r<​sub>​s</​sub>​from this current as ohms. How does this r<​sub>​s</​sub>​ compare to the from the test data? Change the value of R<​sub>​1</​sub>​ from 4.7 KΩ to 2.2 KΩ and re-measure the output impedance of the circuit. How has it changed and why? Plot the measured voltage amplitude seen at the source. The nominal source current in M<​sub>​1</​sub>​ is (Vn - V<​sub>​GS</​sub>​) / 4.7KΩ or 720uA. We can calculate r<​sub>​s</​sub>​from this current as ohms. How does this r<​sub>​s</​sub>​ compare to the from the test data? Change the value of R<​sub>​1</​sub>​ from 4.7 KΩ to 2.2 KΩ and re-measure the output impedance of the circuit. How has it changed and why?
university/courses/electronics/electronics-lab-11m.txt · Last modified: 25 Aug 2017 11:05 by amiclaus