Difference between revisions of "Chapter 6"
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−  ===Digital Logic=== 
+  ===Digital Logic Gates=== 
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+Boolean Algebra 
+Boolean Algebra 

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−  +  ===De Morgan Laws & NAND Equivalent Gates=== 

−  +  *"If the variables in a logic expression are replaced by their inverses, and if the AND operation is replaced by OR, the OR operation is replaced by AND, and the expression is inverted, the resulting logic expression yields the same values as before the changes."<ref>Electronics p.353</ref> 

−  +  *It is possible to create any combinatorial logic function with solely NAND (or NOR) gates 

−  +  { class="wikitable" border="1" style="textalign:center" 

−  +  !Gate!!Symbol!!NAND equivalent 

−  +   

−  +  Inverter<math>\overline{A}</math><math>\overline{AA}</math> 

+   

+  AND<math>AB</math><math>\overline{(\overline{A}+\overline{B})}</math> 

+   

+  OR<math>A+B</math><math>\overline{(\overline{A} \, \overline{B})}</math> 

+  } 

+  
+  ===CMOS Inverter=== 

+  *Zero static power consumption 

+  *<math>KP_p=\frac{1}{2}KP_n</math>, thus <math>\frac{W}{L}_p=2\frac{W}{L}_n</math> to maintain symmetric transfer characteristics. 

+  
+  ===Questions=== 

+  *p.365: Why even have R_on? 

+  *p.377: What problems are there with the NMOS pullup? 

+  *p.382: For CMOS, are the transistors in Triode or Saturation when they're in the "ON" state? How can we tell? 

+  
+  ===References=== 

+  <references/> 
Latest revision as of 22:00, 24 March 2010
Contents
Digital Logic Gates
A  B  NAND 
NOR 
XOR 

0  0  1  1  0 
0  1  1  0  1 
1  0  1  0  1 
1  1  0  0  0 
De Morgan Laws & NAND Equivalent Gates
 "If the variables in a logic expression are replaced by their inverses, and if the AND operation is replaced by OR, the OR operation is replaced by AND, and the expression is inverted, the resulting logic expression yields the same values as before the changes."<ref>Electronics p.353</ref>
 It is possible to create any combinatorial logic function with solely NAND (or NOR) gates
Gate  Symbol  NAND equivalent 

Inverter  
AND  
OR 
CMOS Inverter
 Zero static power consumption
 , thus to maintain symmetric transfer characteristics.
Questions
 p.365: Why even have R_on?
 p.377: What problems are there with the NMOS pullup?
 p.382: For CMOS, are the transistors in Triode or Saturation when they're in the "ON" state? How can we tell?
References
<references/>