Features

• Low Quiescent Current: 8μA Operating
• Withstands Surge Voltage Up to the MOSFET Limit
• Wide Operating Voltage Range: 4V to 72V
• Overcurrent Protection
• Selectable Internal 31.5V/50V or Adjustable Gate Clamp Voltage (Table 1)
• Reverse Input Protection to –60V
• Adjustable Turn-On Threshold
• Adjustable Fault Timer with MOSFET Stress Acceleration
• Controls N-Channel MOSFET
• Latchoff and Retry Options (Table 1)
• Low Retry Duty Cycle During Faults (Table 1)
• 10-Pin DFN (3mm × 3mm) and MSOP Packages

Typical Application

Description

The LTC®4380 low quiescent current surge stopper protects loads from high voltage transients. Overvoltage protection is provided by clamping the gate voltage of an external N-channel MOSFET to limit the output voltage to a safe value during overvoltage events such as load dump in automobiles. Fixed gate clamp voltages are selectable for 12V and 24V/28V systems. For systems of any voltage up to 72V, use the adjustable gate clamp versions. Overcurrent protection is also provided.

An internal multiplier generates a TMR pin current proportional to V_DS and I_D, so that operating time in both overcurrent and overvoltage conditions is limited in accordance with MOSFET stress.

The GATE pin can drive back-to-back MOSFETs for reverse input protection, eliminating the voltage drop and dissipation of a Schottky diode solution. A low 8μA operating current permits use in always-on and battery powered applications. An accurate ON pin comparator monitors the input supply for undervoltage (UV) conditions and also serves as a shutdown input, reducing the quiescent current to 6μA.