To use MOSFET device as a Capacitor



To use MOSFET device as a Capacitor:

Let us use  nMOSFET device here for discussion. 

Use the Figure 26 for the working of nMOSFET as a Capacitor.

Figure 26: MOSFET(n) as Capacitor - Accumulation region

The following points to be noted:

  1. The Source, Drain and the Bulk/Body terminals are grounded

  2. The Gate voltage applied is variable 

  3. For Gate Voltage less than the Threshold Voltage, the transistor operates in the sub-threshold region

  4. For Gate Voltage equal to or greater than the Threshold Voltage, the inversion layer starts developing in the transistor.