The HYM1422 is an integrated 2.7V to 12V hot swap controller. This device allows a board to be safely inserted and removed from live backplanes. This is achieved using a pass FET with a current control loop that using a sense resistor, we can monitor the input current. The board supply voltage can be ramped up at a programmable rate using an external N-channel MOSFET and capacitor. The RESET pin output can be used to generate a system reset when the supply voltage falls below a programmable voltage. The ON pin is the control input for the device and also acts as a soft reset.
HYM1422 Hot Swap Controller circuit schematic
This device can be used in many application such as Hot-Swap/Plug/Dock Power Management, Network Switches, Routers, Hubs, and Electronic Circuit Breaker.

This device also supported with many features such as provide safe hot swap for +2.7V to +12V power supplies with few external components, user-programmable supply voltage power-up rate, charge pumped gate drive for external N-FET switch, undervoltage lockout, soft reset input and glitch filter on RESET, programmable circuit breaker, and system reset output with programmable delay. This device also available in 8-pin PDIP and SOP packages. [Source: Haoyu Microelectronics]