SMH4814

SMH4814 www.DataSheet4U.com Preliminary Information 1 (See Last Page) INTRODUCTION The SMH4814 is an integrated power controller designed to control the hot-swapping of plug-in cards in a distributed power environment. The SMH4814 drives external power MOSFET switches that connect the supply to the load while reducing in-rush current and providing over-current protection. When the source and drain voltages of the external MOSFETs are within specification the SMH4814 asserts the four PUP logic outputs in a programmable cascade sequence to enable the DC/DC converters. The SMH4814 also monitors two independent –48V feeds. The redundant power supplies allow for high availability and reliability. The traditional method of supplying power from these feeds is via ORing power diodes, which consume a significant amount of power. The SMH4814 allows low-RDSON FETs to be used in place of ORing diodes to reduce power consumption. The SMH4814 determines when at least one of the –48V feeds is within an acceptable voltage range and switches on the appropriate FET path while providing slew rate control. The SMH4814 continuously monitors the incoming feeds and switches to the most negative feed as necessary. The SMH4814 is programmed and controlled using the I2C bus as required in ATCATM applications. Dual Feed Active-ORing Programmable Hot Swap Controller FEATURES AND APPLICATIONS Eliminates Passive ORing Diodes for Reduced Power Consumption High Noise Immunity on All Logic Inputs Soft Star...