Digital Electronics (50 per cent only)

Lecturer: Dr I.M. Leslie (iml@cl.cam.ac.uk)

No. of lectures + practicals: 11 + 7  

Introduction, combinational and sequential logic.

The parts of a simple computer. Idealised logic gates. Boolean Algebra describes ideal combinational circuits. Simplification of combinational functions. Sequential logic, flip-flops and delays. Basis for a sequential machine. Fundamental and pulse mode. State reduction and assignment. Real logic gates with varying delays using non-binary signals. Hazards and races. A notation for design. Examples of practical logic circuits.

Synchronous and asynchronous circuits.

Synchronous feedback counters, higher-level components, encoders, decoders, selectors, multiplexers and demultiplexers. Simple bus arrangements. Programmable logic arrays. The synchronisation problem and how to cope with it. Asynchronous, speed-independent and self-timed circuits. Emerging ideas for the design of self-timed circuits.

Technology.

Semiconductors, patterning and processing. Holes and electrons, junctions, depletion layers. Devices and their properties. Bipolar and unipolar circuits. Speed, scale of integration and applications. An example of domino logic in a self-timed multiplier.

Recommended books:

Dowsing, R.D. & Woodhams, F.W.D. (1990). Computers from Logic to Architecture. Chapman and Hall.

Lewin, M.H. (1983). Logic Design and Computer Organization. Addison-Wesley (out of print).

Hayes, J.P. (1993). Introduction to Digital Logic Design. Addison-Wesley.

Mead, C. & Conway, L. (1980). Introduction to VLSI Systems. Addison-Wesley.

Katz, R.H. (1994). Contemporary Logic Design. Benjamin/Cummings.