Keep your boss from worrying
If your current project exhausts all normal design time plus allowable extra
time, here are some tips to overcome management worries.
Blame problems on
High or low frequency, parasitic, load, layout, or heat related. Or,
blame computer simulation that showed no stability problems.
Everything was working until you closed the loop. A complex pole for
compensation may be required.
Call attention to crosstalk that you could not have checked at the
prototype stage. Note sagely that the problem is probably either intrinsic
or extrinsic. Point out that adding optoisolators or shielding will take
Blame jitter on components, terminations, transmission lines, speed,
interfaces - or just cite jitter without offering explanation.
Blaming inadequate heat sinking or airflow is a good idea. "Typical
drift" is a good excuse, too.
If you did not do the board layout, then place the blame on mistakes
in the ground plane, ground loops, etc. If using a multilayer board, buy
more time by maintaining that mistakes in a hidden layer make a completely
new layout necessary.
The samples and prototypes arrived late.
If these suggestions do not work, don't give up. Try glitches, overshoot
or undershoot, static charges, threshold, hysteresis, and power supply
problems (only if you did not design the power supply, of course). Then
ask for the most expensive test instruments, computers, and software packages
available. Failing all else, demand that management rewrite your project's
specifications because the specs are obviously too tight. Finally, let the
software department develop workarounds for your hardware problems.
EDN Magazine, July 4 1991