EE3300/EE5300 Electronics Applications
Why neatness matters

Written by A/Prof Bronson Philippa and Luke McCarthy
College of Science and Engineering, James Cook University
Last updated 7 February 2025

Case 1

Figure 1
Figure 1:

A neatly constructed current mirror and differential pair.

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Figure 2
Figure 2:

AC-coupled oscilloscope measurement of the output from the neatly constructed differential pair. The input was a sine wave of sufficient magnitude to saturate the differential pair. Notice the swing is is approximately 2 V as can be calculated from the circuit.

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Case 2

Figure 3
Figure 3:

An alternative construction of the differential pair (and the rest of the circuit).

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Figure 4
Figure 4:

Measurement of the differential pair output for the circuit shown in Figure 3. Notice the additional noise on the low voltage side and the worse rise-fall times.

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Summary

  • Always connect directly to the power rails and place decoupling caps close to the sensitive circuits.
  • Keep signal paths short. Cut the wires to the length that you need.
  • Cut resistor legs so they can be pressed neatly down into the board.
  • Sometimes it’s better to twist unshielded wires together like the red and black from the function generator in Figure 1 (or maybe it’s just superstition).