The STEF12 is an integrated electronic fuse optimized for monitoring output current and input voltage. Connected in series to a 12 V rail, it is capable of protecting the electronic circuitry on its output from overcurrent and overvoltage. The device has a controlled delay and turn-on time. When an overload condition occurs, the STEF12 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 power is re-applied the E-fuse initially limits the output current to a safe value and then again goes into an open state. The device is equipped with a thermal protection circuit. The intervention of the thermal protection is signalled to the board monitoring circuits through a signal on the Fault pin. Unlike the mechanical fuses, which must be physically replaced after a single event, the E-fuse does not degrade in its performance after short-circuit/thermal protection interventions and it is reset either by recycling the supply voltage or using the Enable pin. The companion chip for the 5 V power rails is also available with part number STEF05.
- Continuous current (typ): 3.6 A
- N-channel on-resistance (typ): 53 mΩ
- Enable/Fault functions
- Output clamp voltage (typ):15 V
- Undervoltage lockout
- Short-circuit limit
- Overload current limit
- Controlled output voltage ramp
- Thermal latch (typ): 165 °C
- Uses tiny capacitors
- Operating junction temp. - 40 °C to 125 °C
- Available in DFN10 (3x3 mm) package
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