LTC4279IUFD#PBF

LTC4279 is a autonomous single port power sourcing equipment (PSE) controller designed for use in IEEE 802.3at type 1, type 2 and LTPoE++ compliant power over ethernet (PoE) systems. It provides fully autonomous IEEE 802.3 and LTPoE++ compliant operation without a microcontroller. It simplifies PSE implementation, requiring only a single supply and a small number of passive support components. It delivers lowest-in-industry heat dissipation by utilizing a low-RDS(ON) external MOSFET and a 0.1 ohm sense resistor, eliminating the need for expensive heat sinks and increasing efficiency. PD discovery uses a proprietary dual-mode 4-point detection mechanism ensuring excellent immunity from false PD detection. Midspan PSEs are supported with physical layer classification and a 2.5 second backoff timer. It is widely used in applications such as PoE PSE endpoints (switch/router), PoE midspan power injectors, power forwarders, femto cells, security systems etc.

• Supports LTPoE++® upto 90W, supports dual-signature PDs
• Robust short-circuit protection, status LED pin
• Classification dependent ICUT and ILIM current thresholds
• Supports 2-pair and 4-pair output power
• Pin-selectable detection backoff timer for midspans
• Pin programmable legacy PD detection
• Pin programmable maximum power mode
• VEE supply current is -1.7mA typical at (AGND – VEE = 55V, TA = 25°C)
• Operating temperature is -40°C to 85°C
• Package style is 20-lead plastic QFN

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party