Hot-swap capability is an absolute requirement in many bus-based systems in applications ranging from industrial control to IT servers. With the new LTC4222, Linear Technology targets hot-swap designs with a two power supplies. The controller can protect boards with supply voltages between 2.9V and 29V -- allowing safe insertion and removal from live backplanes.
Plugging a board into a hot backplane can cause problems because inrush currents create a glitch on the load supplies and can harm other boards in the system. The LTC4222 is designed to connect with N-channel MOSFETs and control the inrush current. The IC also includes a 10-bit ADC and I2C interface that allow software monitoring of power consumption and operational status, and execution of diagnostics.
Linear offers the device in commercial and industrial versions, in 32-pin QFN and 36-lead SSOP packages. The ICs cost $5.85 (1000).