LTC9101-2A/LTC9102 Power Sourcing Equipment (PSE) Controller

ADI's LTC9101-2A and LTC9102 chipset is up to a 48-port power sourcing equipment (PSE) controller designed for use in IEEE 802.3at Type 1 and 2 compliant Power over Ethernet (PoE) systems. The LTC9101-2A and LTC9102 are designed to power 802.3af and 802.3at compliant PDs. These chipsets deliver low industry heat dissipation using low R_DS(ON) external MOSFETs and 0.1 Ω sense resistance per power channel. A transformer-isolated communication protocol replaces expensive optocouplers and a complex isolated 3.3 V supply, resulting in significant cost savings in the bill of materials (BOM).

Advanced power management features include per-port 14-bit current/voltage monitoring, programmable current limits, and versatile fast shutdown of preselected ports. PD detection uses a proprietary multipoint detection mechanism, ensuring excellent immunity from false PD identification. One-event and two-event physical classifications are supported. The LTC9101-2A and LTC9102 include an I²C serial interface operable up to 1 MHz. They are pin or I²C programmable to negotiate PD-delivered power up to 25.5 W.