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Level Restoring
to reduce static power

  1. pass transistors used in interconnect
    • lose Vt voltage on "logic high"
  2. problem: static power
    • downstream logic and buffers leak
  3. possible solutions
    • gate boosting - unreliable
    • multiple Vt design - unavailable
    • level restoring
  4. level restoring works
    • sensitive to transistor sizing
    • falltime increases (fights restoring pullup)
    • problem: falltime can be infinity!!