Analog Circuitry used in Flash Memory Circuits

[snoop835]

site:edaboard.com high voltage management

What are the analog circuitry that is used in Flash Memory circuits?

What is Floating Gate MOSFET? How does it differ from conventional MOSFET?
Is there any good reading materials for this topic?

thanks

 

[extraord]

the analog parts of flash memory mainly have two parts.
one is sense amplifier. and other is charge pump.
u can search the ieee paper writen by ST flash group. 2003.
also there is some books ,u can search it on amazon.

the float gate mos is much complex than normal mos. the principle is simple. but the accurate model of program or erase is difficult to get, almos impossible.

 

[Btrend]

1. high voltage manipulation
2. regulator
3. negative voltage manipulation
4. current comparator or voltage comparator
5. reference generation
6. voltage sequence of "program" and "erase"

 

[jackjtchan]

A. Internal high voltage management:
a. Charge pump: positive and negative
b. Regulator
c. Bias generator (voltage bias: bandgap reference, tyipcal; current bias: current mirror)
d. Voltage boost (for read operation)
e. Current limitter (avoiding latch-up)
B. HV switches -- for well-bias control and WL voltage switch
C. Sensing path:
a. Current/Voltage comparator
b. I-V converter
D. Output driver (typical const. current driver to reduce the noise)

All these circuits are control by the internal logic core.

 

[aminmahdi]

hi

 

[A.Anand Srinivasan]

the main idea behind floating gate MOS is that charge carriers are embedded on the Gate SiO2 layer using current.... so the MOS becomes insensitive to the voltage applied to its gate and it denotes the fuse blown state...
when it is to be erased they apply a quick high potential and extract out the charge carriers...

 

[cougar168]

A. Internal high voltage management:
a. Charge pump: positive and negative
b. Regulator
c. Bias generator (voltage bias: bandgap reference, tyipcal; current bias: current mirror)
d. Voltage boost (for read operation)
e. Current limitter (avoiding latch-up)
B. HV switches -- for well-bias control and WL voltage switch
C. Sensing path:
a. Current/Voltage comparator
b. I-V converter
D. Output driver (typical const. current driver to reduce the noise)

All these circuits are control by the internal logic core.

Very well said, everything is controlled by the State Machine; if it is MLC, it will be more sophisticated...