PoE IC meets power demands of LTE picocell basestations
Delivering 123W over 1Gbit/s CAT5e cable, the LTC4279 single-port PoE (Power over Ethernet) controller from Linear Technology is designed for power hungry applications such as LTE picocell base stations, LED signage, security monitoring systems, home automation and machine vision systems.
The LTC4279 includes all legacy (up to 13W), IEEE 802.3at Type 1 (13W) and Type 2 (25.5W) power devices, the company’s proprietary LTPoE++ (up to 90W), and custom (up to 123W) power devices. Two- and four-pair output topologies are supported, as well as single- and dual-signature architectures. Resistor-adjustable power selection allows the IC to be configured for multiple sockets, simplifying design and bill of materials.
Autonomous operation is provided for a variety of power sourcing equipment, including endpoints and mid-span power injectors. A low power sense resistor and external MOSFET simplify thermal design, whereas traditional power sourcing equipment uses MOSFETs which are less robust with higher RDS(ON), says the company. Power devices are discovered using a four-point detection mechanism that ensures best-in-class immunity from false detection. The IC provides a set of classification mechanisms to enable wide system compatibility. Robustness is reinforced with classification-dependent current cut-off and limit thresholds, short-circuit protection and ±80V cable surge protection.
The LTC4279 is offered in the industrial temperature grade (–40 to +85°C) and is available in RoHS-compliant 4.0 x 5.0mm QFN-20 and SO-16 packages.