Overvoltage & Overcurrent Protection

In automotive, industrial and avionic applications, high voltage power supply spikes and surges with durations ranging from a few microseconds to hundreds of milliseconds are commonly encountered. The electronics within these systems must not only survive these transient voltage surges, but in many cases also operate reliably throughout the event. In systems where power is distributed over long wires, severe transients are generated by load steps. Corroded connections between a power source and load can lead to an abrupt interruption of current flow, and a high value of dI/dt. The best example of this condition is automotive load dump, where there is a sudden break in the connection to the battery caused by vibration and corroded terminals. These transients pose a difficult challenge for engineers trying to protect sensitive electronics.

Historically, overvoltage and overcurrent protection (e.g., load dump protection) was achieved using bulky capacitors, TVS diodes and fuses, but this discrete solution consumes a lot of real estate, and does not offer continuous operation through transient events. Linear Technology's family of High Voltage Surge Stoppers, Overvoltage Protection, Overcurrent Protection and Circuit Breaker ICs offer solid front-end protection in small, low power, easy to design solutions that increase system reliability. Circuits can be designed to meet many of the automotive, military, and avionic standards including ISO-7637-2, MIL-STD-1275 and DO-160. These protection ICs are also intended for intrinsically safe equipment that must operate in hazardous environments, where the amount of power dissipated must be limited under normal or abnormal operating conditions to prevent explosions caused by the ignition of hazardous gases.

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