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university:courses:electronics:electronics-lab-8m [24 Jul 2017 15:22] – change amplitude value to peak-peak Antoniu Miclausuniversity:courses:electronics:electronics-lab-8m [25 Jun 2020 22:07] (current) – external edit 127.0.0.1
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-====== Activity 8M. Stabilized current source (NMOS) ======+====== ActivityStabilized current source (NMOS) ======
  
 ===== Objective: ===== ===== Objective: =====
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 ===== Hardware Setup: ===== ===== Hardware Setup: =====
  
-The waveform generator should be configured for a 1 KHz triangle wave with 4 volt amplitude and 2V offset. The input of scope channel 2 (2+) is used to measure the stabilized output current at the drain of M<sub>2</sub>.+{{:university:courses:electronics:nmos_stabilized_cs-bb.png|}} 
 + 
 +<WRAP centeralign> Figure 2 Stabilized current source Breadboard Circuit </WRAP> 
 + 
 +The waveform generator should be configured for a 1 KHz triangle wave with 4 volt amplitude peak-to-peak and 2V offset. The input of scope channel 2 (2+) is used to measure the stabilized output current at the drain of M<sub>2</sub>.
    
 ===== Procedure:===== ===== Procedure:=====
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 The zero gain amplifier can be used to create a stabilized current source. Because the voltage seen at the drain of transistor M<sub>1</sub> is now more constant with changes in the input supply voltage as represented by AWG1, it can be used as the gate voltage of M<sub>2</sub> to produce a much more constant current in transistor M<sub>2</sub>. The zero gain amplifier can be used to create a stabilized current source. Because the voltage seen at the drain of transistor M<sub>1</sub> is now more constant with changes in the input supply voltage as represented by AWG1, it can be used as the gate voltage of M<sub>2</sub> to produce a much more constant current in transistor M<sub>2</sub>.
  
-<WRAP centeralign> Figure M<sub>2</sub> drain current vs. W1 voltage </WRAP>+<WRAP centeralign>{{:university:courses:electronics:nmos_stabilized_cs.png?500|}}</WRAP> 
 + 
 +<WRAP centeralign> Figure M<sub>2</sub> drain voltage vs. W1 voltage </WRAP>
  
 ===== Questions: ===== ===== Questions: =====
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 The output current has a narrow peak. How could multiple copies of the peaking current source be combined to produce a much wider, flatter peak?  The output current has a narrow peak. How could multiple copies of the peaking current source be combined to produce a much wider, flatter peak? 
 +
 +<WRAP round download>
 +**Resources:**
 +  * LTspice files: [[downgit>education_tools/tree/master/m2k/ltspice/mos_stab_curr_source_ltspice | mos_stab_curr_source_ltspice]]
 +  * Fritzing files: [[downgit>education_tools/tree/master/m2k/fritzing/mos_stab_cs_bb | mos_stab_cs_bb]]
 +</WRAP>
  
 **Return to Lab Activity [[university:courses:electronics:labs|Table of Contents]]** **Return to Lab Activity [[university:courses:electronics:labs|Table of Contents]]**
  
university/courses/electronics/electronics-lab-8m.1500902551.txt.gz · Last modified: 24 Jul 2017 15:22 by Antoniu Miclaus