Solid State memory

[Cogman]

Ok, how does it work? I mean, how does storage without and moving parts (electrons not included ) work? I have been wondering this for some time now and I just can figure how solid memory stores when the power goes out.

 

[PrincessGuard]

I assume you mean non-volatile memory since all RAM is solid-state

There are many ways to do this. For example, NVRAM can be made of an array of floating-gate transistors. They are like normal MOSFETs but have an additional insulated "gate" between the channel and the connected gate. The purpose of the floating gate is to change the threshold voltage of the transistor. Putting a negative charge on the floating gate will increase the threshold voltage of an n-channel FET; removing charge will decrease the threshold voltage.

So, if you put a large enough charge on the floating gate, you can make it so that the FET will not conduct under normal operating voltages. This gives you a logical 0 (or 1, I don't know what's actually used). A FET that has an uncharged floating gate will conduct, giving the opposite logic.

The trick is that the floating gate is insulated all around, so there is nowhere for the charge to go even when there is no power (well, the charge will eventually drain away due to oxide breakdown and whatnot). That's how you store data.

The actual charging and discharging (writing and erasing) is done through quantum tunneling, i.e. apply a large enough electric field and electrons will jump through the oxide into/out of the floating gate.

 

[GoHAnSoN]

Originally posted by: PrincessGuard
I assume you mean non-volatile memory since all RAM is solid-state

There are many ways to do this. For example, NVRAM can be made of an array of floating-gate transistors. They are like normal MOSFETs but have an additional insulated "gate" between the channel and the connected gate. The purpose of the floating gate is to change the threshold voltage of the transistor. Putting a negative charge on the floating gate will increase the threshold voltage of an n-channel FET; removing charge will decrease the threshold voltage.

So, if you put a large enough charge on the floating gate, you can make it so that the FET will not conduct under normal operating voltages. This gives you a logical 0 (or 1, I don't know what's actually used). A FET that has an uncharged floating gate will conduct, giving the opposite logic.

The trick is that the floating gate is insulated all around, so there is nowhere for the charge to go even when there is no power (well, the charge will eventually drain away due to oxide breakdown and whatnot). That's how you store data.

The actual charging and discharging (writing and erasing) is done through quantum tunneling, i.e. apply a large enough electric field and electrons will jump through the oxide into/out of the floating gate.

humn...i wonder if this might be too detail for him

just imagine lightbulbs. when a lightbulb flash with light it's 1 , when none, 0.
so, without power, nothing flashes. no memory.
simple enough ?

 

[Cogman]

Thank you gohan, But I understand Binary quite well And dont need another Explanation of it. His definition is exactly what I was lookin for and I thank him for giving me that. Im sorry if I sound rude, but I felt the distinct impression that you where treating me like a noob that could not tell the diffrence Between RDRam and DDR.

 

[petey117]

hmmm,
try this on for size (flash memory)

picture a jail cell (or hundreds lined up next to each other)
inside the jail cell are 2 or 3 electrons - this signifies a zero in binary
or
inside the jail cell are 4 or more electrons - this signifies a 1 in binary

the trick is, when the power is on, the cell can be opened, electrons can be added or removed to chenge the value of what is in them. the door is then closed. once power is off, the doors cannot be opened.

and there you go...

 

[Jeff7]

Originally posted by: petey117
hmmm,
try this on for size (flash memory)

picture a jail cell (or hundreds lined up next to each other)
inside the jail cell are 2 or 3 electrons - this signifies a zero in binary
or
inside the jail cell are 4 or more electrons - this signifies a 1 in binary

the trick is, when the power is on, the cell can be opened, electrons can be added or removed to chenge the value of what is in them. the door is then closed. once power is off, the doors cannot be opened.

and there you go...

It's an unusual jail though - the inmates will always return to their cells when required to.

 

[Mday]

current RAM uses capacitance to store data, that's why it has to be refreshed so often due to leakage. there are other types of RAM which dont do this, MRAM for example uses a magnetic field, much like old RAM.

FLASH memory uses a floating gate.