New Industry Products

Maxim Unveils Quad PSE Controller For High-Power (PoE+) and IEEE 802.3af Applications

September 26, 2007 by Jeff Shepard

Maxim Integrated Products introduced the MAX5952, a quad Power-Sourcing-Equipment (PSE) controller for high-power (PoE+) and IEEE 802.3af-compliant Power-over-Ethernet (PoE) applications. The MAX5952 allows multiport, high-power PoE+ systems to deliver up to 45W of power over the standard Ethernet cable to power devices such as IP phones with color LCD displays, wireless LAN access nodes, and IP cameras.

While the MAX5952 meets the 802.3af standard, this new PSE controller is particularly designed for today’s more demanding, high-power (up to 45W) PoE+ applications. The MAX5952 operates from 32V to 60V, and provides 802.3af powered-device (PD) discovery and classification. It also supports both dc and ac load-disconnect detection methods.

The MAX5952 incorporates Class 4 and Class 5 classification for high-power PDs. An integrated 9-bit analog-to-digital converter (ADC) and with an I2C-compatible, 3-wire serial interface monitors and reports the current drawn by each of the four ports.

Numerous programming and configuration options are claimed to give the MAX5952 unmatched design flexibility. The device can be controlled with a system microcontroller like the MAXQ2000, or configured to operate autonomously in manual or semi-automatic modes. The device can be configured for both endpoint (LAN switches/routers) and midspan (power injectors) PSE applications. The controller’s gate-charging current, current-limit threshold, startup timeout, overcurrent timeout, and autorestart duty cycle are all programmable.

The MAX5952 is pin compatible with the MAX5945 PSE controller and other 802.3af PSE controllers on the market. The MAX5952 is thus backwards compatible with 802.3af-compliant systems. The company claims that, with minimal external component modifications or added cost, designers can upgrade existing systems for higher power.

The MAX5952 has the standard features expected of a PSE controller: input undervoltage lockout detection (UVLO), load-stability safety check during detection, overtemperature protection, output voltage slew-rate limit during startup, power-good and fault status.

Reference designs for both endpoint PSE and midspan PSE applications are available now. The midspan reference design supports up to 192 ports and includes the MAXQ2000 microcontroller and supporting software. Production samples and evaluation (EV) kits are also available.

The MAX5952 is packaged in a 36-pin SSOP and rated to operate in the upper commerical temperature range (0 to +85°C). Pricing starts at $6.33 (1000-up FOB USA).