Features

• Low Loss Replacement for Power Diode
• Controls N-Channel MOSFET
• 0V to 18V Supply ORing or Holdup
• 0.5μs Turn-On and Turn-Off Time
• Undervoltage and Overvoltage Protection
• Open MOSFET Detect
• Status and Fault Outputs
• Hot Swappable
• Reverse Current Enable Input
• 12-Pin MSOP and DFN (3mm × 3mm) Packages

Typical Application

Description

The LTC4352 creates a near-ideal diode using an external N-channel MOSFET. It replaces a high power Schottky diode and the associated heat sink, saving power and board area. The ideal diode function permits low loss power ORing and supply holdup applications.

The LTC4352 regulates the forward voltage drop across the MOSFET to ensure smooth current transfer in diode-OR applications. A fast turn-on reduces the load voltage droop during supply switch-over. If the input supply fails or is shorted, a fast turn-off minimizes reverse currents.

The controller operates with supplies from 2.9V to 18V. For lower voltages, an external supply is needed at the V_CC pin. Power passage is disabled during undervoltage or overvoltage conditions. The controller also features an open MOSFET detect circuit that flags excessive voltage drop across the pass transistor in the on state. A REV pin enables reverse current, overriding the diode behavior when desired.