Patent ID: 7324316

Claim:
A hot-swap circuit system for fan tray module comprising: a soft-start circuit module having a voltage input terminal for receiving an input voltage, which comprises: at least one diode for conducting a current in a single direction, a first bipolar transistor having an emitter grounded, a first field effect transistor turned off when the input voltage changes from a non-zero value to a zero value, a first capacitor having a first terminal electrically connected to a drain of the first field effect transistor and having a second terminal grounded, and discharging when the input voltage changes from the non-zero value to the zero value, a second capacitor discharging when the input voltage changes from the non-zero value to the zero value, and a first Zener diode electrically connected to the second capacitor in parallel; a discharging circuit module electrically connected to the first capacitor in parallel and flowing a discharging current of the first capacitor therethrough; an over-voltage protection circuit module electrically connected to the first capacitor in parallel; and an over-current protection circuit module electrically connected to the first capacitor in parallel, and having a voltage output terminal electrically connected to the fan tray module.