Page 132 - Troubleshooting Analog Circuits

Nasty Latches I19

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Figure 9.6. Installing antireversal diodes in the system power supplies and also on each PC board greatly
reduces the chances of damaging the supplies or the circuitry with inadvertent short circuits
or polarity reversals.

I certainly do not want to say that technicians can’t troubleshoot oscillations
simply because they don’t know the fheory of why circuits oscillate-that’s not my
point at all. I will only argue that a green or insensitive person, whether a technician
or an engineer, can fail to appreciate when a circuit is getting much too close to the
edge of its safety margins for comfort. Conversely, everyone knows the tale of the
old-time unschooled technician who saves the project by spotting a clue that leads to
a solution when all the brightest engineers can’t guess what the problem is.

References

I. Linear Brief LB-32, Microvolt Comparator. in NSC Linear Applicafions Book, 1980-1990