Basic question: what components do flash memory chips use?

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Joseph Beasley 1

Joined Feb 16, 2017
14
Simple question: what is the prime component of flash memory chips?
Is it transistor based or something else?

The reason that I ask is I've wondered how is it a chip can contain so many individual gates; circuits on the scale they are integrated? For instance, though an SD card is not a microprocessor, if you compare the # of individual transistors and gates and say the integration level is 45nm. How is it a memory chip can have close to the same number of transistors as an expensive microchip like a CPU and still be viable to manufacture?
If the flash chip can hold 1tb, isn't that like a few billion transistors/ res/ capacitors etc?

Am I understanding this wrong?
 
Last edited:

joeyd999

Joined Jun 6, 2011
4,477
Simple question: what is the prime component of flash memory chips?
Is it transistor based or something else?

The reason that I ask is I've wondered how is it a chip can contain so many individual gates; circuits on the scale they are integrated? For instance, though an SD card is not a microprocessor, if you compare the # of individual transistors and gates and say the integration level is 45nm. How is it a memory chip can have close to the same number of transistors as an expensive microchip like a CPU and still be viable to manufacture?
If the flash chip can hold 1tb, isn't that like a few billion transistors/ res/ capacitors etc?

Am I understanding this wrong?
https://en.m.wikipedia.org/wiki/Flash_memory
 

dl324

Joined Mar 30, 2015
12,786
How is it a memory chip can have close to the same number of transistors as an expensive microchip like a CPU and still be viable to manufacture?
The topology used in memory chips is very regular and repeated. That allows the memory cell to be designed for high yield and they can usually use a tighter set of design rules. Memory chips can further increase their effective yield by incorporating spare rows and columns that are fused in during test. That can't be done in most areas of a microprocessor.

NAND FLASH chips can ship with defects because that technology requires the use of error correction. That doesn't apply to any other designs. For example, NOR FLASH is end of life after the first bit fails. NAND FLASH is okay as long as the critical block still functions.
 
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