When does MOS act as a memory device?

[pavan_chandolu07]

how the MOSFET acts as memory device, i mean ,at which state it acts as memory device

 

[Old Nick]

Re: MOS as memory device

The gate capacitance of the device will hold a voltage for a while (the same as any capacitor will), as long as there's not a low resistive path to ground. The gate capacitance at the input of source followers are used to sample and hold the coltage from a phododiode in CMOS cameras (Active pixel sensors).
I hope this is clear.

 

[pavan_chandolu07]

Re: MOS as memory device

ya clear thanks 4 ur answer, dat means in all the memory devices the resistance path for the gate is bloked???? , so that it can hold the signal for a long time?????????

 

[Old Nick]

Re: MOS as memory device

not quite sure what you're asking there, but there will be a process dependent leakage current from the gate which will discharge the gate slowly. You can work out the discharge curve from the gate area, leakage current etc. But, depending on conditions a transistor gate will hold a voltage for a few minutes.