**Transfer Characteristics of n-channel Enhancement Type MOSFET**

- The transfer characteristics of a n-channel enhancement MOSFET are as shown in Figure.
- Note that the drain current is zero for V
_{GS}≤ V_{TN }For an n-channel E-MOSFET the threshold voltage is denoted by V_{TN}and for a p-channel E-MOSFET the threshold voltage is denoted by V_{TP.} - The transfer characteristics shown in Figure is a characteristic of V
_{GS}Vs I_{D}. It is now totally in the positive V_{GS}region and remains zero till V_{GS}= V_{TN.} - The relation between drain current and V
_{GS}is given by the following equation,

I

_{D }= k (V_{GS}- V_{TN})^{2}- Here k is a constant and its value depends on the construction of the device.
- For n-channel E-MOSFETS the constant is sometimes denoted by k
_{n}and for a p-channel E-MOSFET, it is denoted by k_{p}. - The expression for I
_{D}is a nonlinear relation and it is valid only for V_{GS}> V_{TN.}Therefore the transfer characteristics is also nonlinear.