An Easy Way to Add Auxiliary Control Functions to Hot Swap Cards

A Hot Swap™ controller is essential to any system in 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.

Download the full Design Note as a PDF.