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g m /I D Design Approach. Transconductance. As a voltage-controlled current source, a MOS transistor can be characterized by its transconductance: It is important to know that. What Happens to g m /I D when W and I D are doubled ?. Small Signal Model for NMOS Transistor.
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Transconductance • As a voltage-controlled current source, a MOS transistor can be characterized by its transconductance: • It is important to know that
gm/ID Design Flow Specs Design Equations (Analytical) gm/Id Data Set (Emprical) gm/ID Design Optimization (F. Silveira, JSSC, 1996.) W/L Ratios
Intuition gm gds gm/ID gm/gds 2gm 2gds gm/ID gm/gds 2gm 2gds gm/ID gm/gds
Extended gm/ID Data Set • gm/gds • gm/gmbs • ID/W • Cgd/Cgg • Cgs/Cgg • ….more • γ(thermal noise) • fco(flicker noise) • Distortion parameters (F. Silveira, JSSC, 1996.) (Ou, 2011.)
Calculation (gm is determined)
gm/gds (50)