Analog Devices (Country Manager Hong Sa-kwak) announced that its Power by Linear™ LTC4291/92 isolated 4-port PSE (power source equipment) controller chipset has been recorded as the first PSE controller device to pass the IEEE 802.3bt (PoE++) PoE (Power over Ethernet) compliance test conducted by Sifos Technologies.

PoE fundamentally presents system and network engineers with the challenge of evaluating PSEs. A PSE is a multi-channel intelligent DC power supply that is enabled and disabled through standardized processes without compromising existing Ethernet data transmission capabilities. Along with this, compatibility testing becomes complex due to operational requirements for several supply and polarity configurations.

LTC4291/92

The Sifos 24-port PSA-3000 PowerSync analyzer, equipped with multiple Sifos 2-port PSA3202 test blades, provides complete automated testing and analysis capabilities for LTC4291/92-based PSEs.

A rigorous compatibility test suite, enhanced with special analysis functions, evaluated the LTC4291/92 against the IEEE 802.3at (PoE+) standard, the new 802.3bt standard, and other proprietary standards. These scalable design and test solutions are built upon extensive knowledge of PoE and years of experience, enabling faster time-to-market and rapid deployment of PoE networks when the IEEE 802.3bt standard is officially ratified in 2018.

In tests conducted by Analog Devices itself, the LTC4291/92 PSE chipset passed a wide variety of tests, just as the PSA-3000/3202 solution emulated various IEEE 802.3bt PD (powered devices) products.

The continuous 90W 4-pair PSE loading capability ensures that this PSE can handle the 71.3W maximum PD power level of 802.3bt in single-signature or dual-signature PD configurations. The LTC4291/92 accurately demonstrates all physical layer classes (up to 5 events) required by the new Type 3 and Type 4 PDs, as well as backward compatibility with Type 1 and Type 2 PDs.

For PSEs using the Link Layer Discovery Protocol (LLDP), the PSA-3000/3202 can also emulate and analyze this type of power negotiation.

By using the GUI and scripting environment provided with the device, users can directly configure and interact with these devices. The LTC4291/92 is supported with evaluated schematics, complete reference designs, a QuikEval™ GUI, and example code, while the PSA-3000/3202 can be extended using the PSA Interactive GUI and the PowerShell PSA scripting environment.

The LTC4291/92 chipsets are available in commercial and industrial temperature ranges. The LTC4291 digital controller is available in a RoHS-compliant 24-pin 4mm x 4mm QFN package, while the LTC4292 analog controller is available in a 40-pin 6mm x 6mm QFN package. The LTC4291/92 are Analog Devices' first 802.3bt PSE controllers and provide an upgrade path for the popular LTC4266 4-port 802.3at PSE controller.