1-Transistor Memory Cell (DRAM)

• Write:

  • 1. Drive bit line
  • 2. Select row

• Read:

  • 1. Precharge bit line to Vdd (1)
  • 2. Select row
  • 3. Cell and bit line share charges
    • Very small voltage changes on the bit line
  • 4. Sense (fancy sense amp)
    • Can detect changes of ~1 million electrons
  • 5. Write: restore the value

• Refresh

  • 1. Just do a dummy read to every cell.

row select

bit

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