Description
The STEF033 is an integrated electronic fuse optimized for monitoring output current and the input voltage. Connected in series to the 3.3 V rail, it is able to protect the electronic circuitry on its output from overcurrent and overvoltage. The STEF033 has controlled delay and turn-on time. When an overload condition occurs, the device limits the output current to a predefined safe value. If the anomalous overload condition persists, it goes into an open state, disconnecting the load from the power supply. If a continuous short-circuit is present on the board, when the power is re-applied the E-fuse initially limits the output current to a safe value and then goes again into the open state. The voltage clamping circuit prevents the output voltage from exceeding a fixed value, if the input voltage goes beyond this threshold. The device is equipped with a thermal protection circuit. Intervention of thermal protection is signaled to the board-monitoring circuits through an appropriate signal on the Fault

Features
■ Continuous current typ.: 3.6 A (DFN), 2.5 A (Flip Chip)
■ N-channel on resistance (typ): 40 mΩ (DFN), 25 mΩ (Flip Chip)
■ Enable/Fault functions
■ Output clamp voltage (typ): 4.5 V
■ Undervoltage lockout
■ Short-circuit limit
■ Overload current limit
■ Controlled output voltage ramp

Applications
■ Hard disk drives
■ Solid state drives (SSD)
■ Hard disk and SSD arrays
■ Computer
■ DVD and Blu-Ray disc drivers