VDD is not your BFF: Four things you didn’t know could go wrong [Shop Talk: What You Didn’t Learn in School]

Somewhere on your schematic, there is a small circle. It’s probably labeled
VDD
or
AVDD
or something equally innocuous. But that harmless-looking circle embodies the biggest lie in the industry (see
Figure 1
). Nobody knows the full extent of the damage that circle causes, but a conservative guess is that it’s responsible for at least 90% of silicon failures and redesigns. That circle is your power supply. And it is almost certainly doing you wrong.