The Enhancement mode MOSFET's are equivalent to a "Normally Open" switch that requires gate-source voltage to switch ON the device. If the positive voltage (+VGS) is applied to an n-channel gate terminal, then only the channel will conduct and the drain current starts to flow through the channel. If the bias voltage is zero or negative(- VGS) then the transistor switches OFF and the channel stays in the non-conductive state resulting in the drain current to be zero. Transfer characteristics of an n-channel depletion MOSFET is as shown: [ alt="F1 S.B 10.9.20 Pallavi D 6" src="//storage.googleapis.com/tb-img/production/20/09/F1_S.B_10.9.20_Pallavi_D%206.png" style="width: 408px; height: 183px;"> We observe that for VGS = 0, drain current is flowing. Transfer characteristics of p-channel depletion MOSFET is as shown: [ alt="F1 S.B 10.9.20 Pallavi D 7" src="//storage.googleapis.com/tb-img/production/20/09/F1_S.B_10.9.20_Pallavi_D%207.png" style="width: 406px; height: 188px;"> Transfer characteristics of n-channel Enhancement MOSFET is as shown: [ alt="F1 S.B 10.9.20 Pallavi D 8" src="//storage.googleapis.com/tb-img/production/20/09/F1_S.B_10.9.20_Pallavi_D%208.png" style="width: 164px; height: 138px;"> We observe that for VGS = 0, there is no drain current flowing as there is no conduction region at VGS = 0, in enhancement mode MOSFET. Transfer characteristics of p-channel Enhancement MOSFET is as shown: [ alt="F1 S.B 10.9.20 Pallavi D 9" src="//storage.googleapis.com/tb-img/production/20/09/F1_S.B_10.9.20_Pallavi_D%209.png" style="width: 161px; height: 131px;">