LTC4271IUF#PBF

The LTC4271IUF#PBF is a 12-port Power Sourcing Equipment (PSE) Controller designed for use in IEEE 802.3 at type 1 and type 2 (high power) compliant power over Ethernet (PoE) systems. Transformer-isolated communication protocol replaces expensive opto-couplers and complex isolated 3.3V supply resulting in significant BOM cost savings. This chipset delivers lowest-in-industry heat dissipation by utilizing low-RDS(ON) external MOSFETs and 0.25R sense resistors. Advanced power management features include per-port 12?bit current monitoring ADCs, DAC-programmable current limit and versatile fast shut-down of preselected ports. Advanced power management host software is available under a no-cost license. PD discovery uses a proprietary dual-mode 4-point detection mechanism ensuring excellent immunity from false PD detection. Midspan PSEs are supported with 2-event classification and a 2 second backoff timer.