Q. 4.SP.1

If $C_S = 0$ and all else is unchanged in Example 4.2, find the extremes between which $v_S$ swings.

Verified Solution

Voltage $v_{gs}$ will swing along the dc load line of Fig 4-6(b) (which is now identical to the ac load line) from point a to point b, giving, as extremes of $i_D, 3.1 \text{mA}$ and $0.4 \text{mA}$.    The corresponding extremes of $v_S = i_DR_S$ are $6.2 \text{V}$ and $0.8 \text{V}$.