DC2180A: Dual Negative Voltage Ideal Diode - ORing Controller and Monitor

Demonstration circuit 2180A showcases the LTC4371 dual negative voltage ideal diode-OR controller and monitor, in a -48V, 50A application. Each channel includes two paralleled 2mΩ (Max) MOSFETs for a total dissipation of just 2.5W at full load. Power connections are made by way of 1/4" ring terminals with a cable capacity of 4 AWG.

The LTC4371 is a two-input negative voltage ideal diode-OR controller that drives external N-channel MOSFETs as a low dissipation alternative to Schottky diodes in high power -48V systems. Low power dissipation and voltage loss eliminates the need for heatsinks and reduces PC board area. Power sources can be easily OR'd together to increase total system power and reliability.

The LTC4371 tolerates ±300V transients such as those experienced during lightning-induced surges and input supply short-circuits events. The internal shunt regulator and low 300µA quiescent current allow the use of a large value dropping resistor to protect the supply pin against high voltage transients, while the high impedance drain pins can be similarly protected by high value series resistors without compromising diode operation