View
225
Download
0
Category
Tags:
Preview:
Citation preview
Flash Memory…and a tour through FETs
Actual MOSFET Devices
Single MOSFET on Intel chip Enhancement MOSFET
MOSFET Motor Control
Circuit component Motor Control Circuit
Floating Gate MOSFET = Flash
+++++ Assume:VDS =VD - VS =+12V
What happens if?:VGS =VG – VS= +12 V
Then what happens?:to ‘jailed’ electrons ifVGS is set to 0V?
Reading Memory State
Change in Threshold Voltage due to Screening Effect of Floating GateRead mode: Apply intermediate voltage, check whether current is flowing or not
Writing Memory State
Control gate voltage determines whether electrons are injected to, or push/pulled out of floating gate.
Block Structure
Writing block structure: The ole 2-step
Step 1: Set all bits to 1 (clear out electrons from floating gate)Step 2: Set selected bits to 0 (inject electrons from control to floating gate)
1 2
Voila – flash memory stick
Citations/Image Sources• http://www.learnabout-electronics.org/fet_01.php (JFETs)• http://
volga.eng.yale.edu/index.php/Main/Semiconductors#MOSFET• http://www.electronics-tutorials.ws/transistor/tran_7.html
(MOSFET motor control)• http://www.engadget.com/2011/10/31/engadget-primed-ssds
-and-you/
• https://www.youtube.com/watch?v=msi5GDz9JIw (hyperscience youtube channel – reading flash contents)
Recommended