Sneak Path

Emerging Memories Today: Understanding Bit Selectors

Emerging Memory ParadeThe previous post in this series (excerpted from the Objective Analysis and Coughlin Associates Emerging Memory report) explained why emerging memories are necessary.  Oddly enough, this series will explain bit selectors before defining all of the emerging memory technologies themselves.  The reason why is that the bit selector determines how small a bit cell can get, and that is a very significant component of the overall cost of the technology.  Cost, of course, is extraordinarily important because no system designer would use a component that would make a system more expensive than it absolutely needs to be!

A number of the Memory Guy’s readers may never have heard of a selector. I’ll explain it here.  It’s not complicated.

Every bit cell in a memory chip requires a selector.  This device routes the bit cell’s contents onto a bus that eventually makes its way to the chip’s pins, allowing it to be read or written.  The bit cell’s technology determines the type of selector that is appropriate: SRAMs use two transistors, DRAMs use one transistor, and flash memories combine a transistor with the Continue reading