Features

• Shares Load Between Two Supplies
• Eliminates Need for Active Control of Input Supplies
• No Share Bus Required
• Blocks Reverse Current
• No Shoot-Through Current During Start-Up or Faults
• 0V to 18V High Side Operation
• Enable Inputs
• MOSFET On Status Outputs
• Dual Ideal Diode Mode
• 16-Lead DFN (4mm × 3mm) and MSOP Packages

Typical Application

Description

The LTC®4370 is a two-supply current sharing controller which incorporates MOSFET ideal diodes. The diodes block reverse and shoot-through currents during start-up and fault conditions. Their forward voltage is adjusted to share the load currents between supplies. Unlike other sharing methods, neither a share bus nor trim pins on the supply are required.

The maximum MOSFET voltage drop can be set with a resistor. A fast gate turn-on reduces the load voltage droop during supply switchover. If the input supply fails or is shorted, a fast turn-off minimizes reverse current transients.

The controller operates with supplies from 2.9V to 18V. For lower rail voltages, an external supply is needed at the V_CC pin. Enable inputs can be used to turn off the MOSFET and put the controller in a low current state. Status outputs indicate whether the MOSFETs are on or off. The load sharing function can be disabled to turn the LTC4370 into a dual ideal diode controller.