An Easy Way to Add Auxiliary Control Functions to Hot Swap Cards :which boards are inserted into a live backplane. The
controller must gently ramp up the supply voltage and
current into the card’s bypass capacitors, thus minimizing
disturbances on the backplane and to other cards.
Likewise, it must disconnect a faulty card from the
backplane if it draws too much current. The controller
also monitors undervoltage and overvoltage conditions
on the backplane supply, ensuring reliable operation of
the card’s circuitry. The LTC4215-1 takes the obvious
next step and integrates three general purpose I/O (GPIO)
lines and an accurate ADC into the Hot Swap controller
to provide quantitative information on board voltage
and current. Upgrading to the LTC4215-1 is analogous
to replacing a car’s venerable “Check Engine” light with
a modern dashboard information display.