DC1505A

DC1505A demonstration circuit features the LTC®4360, an overvoltage protection controller. The LTC4360 is designed for portable devices with multiple power supply options. During overvoltage transients, the LTC4360 turns off the MOSFET within 1µs, isolating downstream components from the input supply. Inductive cable transients are absorbed by the MOSFET and load capacitance. In most applications, the LTC4360 provides protection from transients up to 80V without requiring transient voltage suppressors or other external components. The LTC4360 has a delayed start-up and adjustable dV/dt ramp-up for inrush current limiting. An active-low PWRGD pin provides power good monitoring for VIN. The LTC4360-1 features a soft shutdown controlled by the active-low ON pin. The LTC4360-2 has a GATEP pin that drives an optional external P-channel MOSFET for negative voltage protection. Following an overvoltage condition, the LTC4360 automatically restarts with a start-up delay.

• LTC4360-1 provides overvoltage protection with ON control for the USB output
• LTC4360-2 with P-MOSFET provides overvoltage and negative-voltage protection
• LTC4360-2 with P-MOSFET adds reverse-current protection to overvoltage and negative protection