CPS 1 - Spring, 1997 - Ramm 3/28/97 #27
- Announce
- Reading: Notes on Communications on WWW
Chapter 6. Electric Circuits
- Binary Addition: Demo
Simulation: This is How a Computer Works
- Conversion to and from Decimal
Chapter 7. Transistors
Chapter 8. Very Large Scale Integrated Circuits
- Problems with Relay Computers
- speed
- power consumption
- reliability
- size & weight
- noise
- Vacuum Tube
- electronic switch
- how it works
- fast
- Problems with Vacuum Tube Computers
- power consumption
- size & weight
- reliability
- noise (cooling)
- speed (~1/size)
- Transistor
- Two basic kinds (also N & P polarities)
- Junction Transistors/Bipolar Transistors
- Junction/Bipolar Transistors
- Historically First
- Size First
- Current amplifiers
- Close to relays
- Current always flowing
- Still uses much power
- Field Effect/Metal Oxide Semiconductor Transistors
- Field Effect/Metal Oxide Semiconductor Transistors
- How an MOS transistor works
- Voltage driven
- Almost no current (CMOS)
- Relate to relay (switch model)
- Integrated Circuits -- VLSI
- Multiple Transistors on a Chip
- Use photo-lithography to "print" wires and transistors
- SSI, MSI, LSI, VLSI
- Now get millions of transistors on 1/4 inch square chip
- Economics of Silicon (Micro-electronics)
- Tremendous cost to produce one chip
- If it works, extra copies almost free
- Do simulations of everything to get it right the first time
- Plant to produce memory chips costs ~$1 Billion