weak inversion in analog and digital circuits - Lund Institute of ...
weak inversion in analog and digital circuits - Lund Institute of ...
weak inversion in analog and digital circuits - Lund Institute of ...
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Weak <strong><strong>in</strong>version</strong><br />
TRANCONDUCTANCE FROM WEAK TO STRONG INVERSION<br />
• Transonductance g m from gate <strong>in</strong> saturation<br />
nU T<br />
g m<br />
I D<br />
<strong>weak</strong> <strong><strong>in</strong>version</strong> asymptote: g m =I D /(nU T )<br />
CSEM, E. Vittoz, 2003<br />
page 10<br />
model a<br />
1.0<br />
0.8<br />
0.6<br />
0.4<br />
model b<br />
strong <strong>in</strong>v.asymptote: gm = 2βID /n<br />
0.2<br />
0<br />
0.01<br />
<strong>weak</strong><br />
0.1<br />
moderate<br />
1<br />
strong <strong>in</strong>v.<br />
10 100<br />
IC=ID /IS • g m /I D decreases with <strong>in</strong>creas<strong>in</strong>g <strong><strong>in</strong>version</strong> coefficient IC.<br />
• g m /I D is maximum <strong>in</strong> <strong>weak</strong> <strong><strong>in</strong>version</strong>.