The LTC4290/LTC4271 chipset is an 8-port power sourcing equipment (PSE) controller designed for use in IEEE 802.3at 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. The LTC4290/LTC4271 chipset delivers lowest-in-industry heat dissipation by utilizing low-RDS(ON) external MOSFETs and 0.25Ω 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. The LTC4290/LTC4271 includes an I2C serial interface operable up to 1MHz. The LTC4290/LTC4271 is available in multiple power grades allowing delivered PD power up to 90W. Applications * PoE PSE Switches/Routers * PoE PSE Midspans * Eight Independent PSE Channels * Compliant with IEEE 802.3at Type 1 and 2 * Chipset Provides Electrical Isolation * Reduced BOM Cost * Eliminates up to 6 High Speed Opto-Couplers * Eliminates Isolated 3.3V Power Supply * Low Power Dissipation * 0.25Ω Sense Resistance Per Channel * Very High Reliability 4-Point PD Detection * 2-Point Forced Voltage * 2-Point Forced Current * VEE and VPORT Monitoring * 1 Second Rolling IPORT Averaging * Supports 2-Pair and 4-Pair Output Power * 1MHz I2C Compatible Serial Control Interface * Available In Three Power Grades * A-Grade – LTPoE++™ 38.7W to 90W * B-Grade – PoE+ 25.5W * C-Grade – PoE 13W * Available In a 40-Lead 6mm × 6mm (LTC4290) and 24-Lead 4mm × 4mm (LTC4271) QFN Package https://elecena.pl/product/3535796/8-port-poe-poe-ltpoe-pse-analog-controller 2012-08-22 https://elecena.pl/product/3535796/8-port-poe-poe-ltpoe-pse-analog-controller 2015-07-16 https://elecena.pl/product/3535796/8-port-poe-poe-ltpoe-pse-analog-controller 2025-01-17