Octal 802.3at PoE PSE Controller

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Lead Time 20 weeks
Unit Price:$6.04
Minumum Qty: 1250
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The Si3459 is a fully-programmable, eight-port power management controller for IEEE 802.3 compliant Power Sourcing Equipment (PSE). Designed for use in PSE endpoint (switches), the Si3459 integrates eight independent ports, each with IEEE-required powered device (PD) detection and classification functionality. In addition, the Si3459 features a fully-programmable architecture that enables powered device (PD) disconnect using a dc sense algorithm, a robust multipoint detection algorithm, software-configurable per-port current and voltage monitoring, and programmable current limits to support the IEEE 802.3at standard. Intelligent protection circuitry includes input under-voltage detection, output current limit, and short-circuit protection. The Si3459 operates by host processor control through a three-wire, I2C-compatible serial interface. Independent serial data input and output pins enable high-voltage isolation through external isolators. An interrupt pin is used to alert the host processor of various status and fault conditions. The device also supports pin-programmable AUTO modes for autonomous operation, without the need for a host processor. The Si3459 also features an on-chip dc-dc converter for creating the digital voltage rail from the PoE voltage, thus enabling single-rail power operation.

• IEEE Power Sourcing Equipment (PSE)
• Power over Ethernet Switches
• IP Phone Systems
• Smartgrid Switches
• Ruggedized and Industrial Switches

Symmetry Electronics is an authorized Silicon Labs distributor.


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Octal-Port Power Sourcing Equipment (PSE) controller
IEEE 802.3at Type I and II compliant
Port priority shutdown control
Adds enhanced features for maximum design flexibility:
Per-port current and voltage monitoring
PoE+ support with programmable current limits
Multi-point detection
Programmable power MOSFET gate drive control
Configurable watchdog timer enables failsafe operation
Maskable interrupt pin
Comprehensive fault protection circuitry includes:
Power under-voltage lockout
Output current limit and short-circuit protection
Thermal overload detection
Pin-programmable AUTO modes
Extended operating temp range: 40 to +85 C
56-pin QFN package (RoHS-compliant)
On-chip dc-dc converter enables single-rail power operation

Previously Viewed Products

Octal 802.3at PoE PSE Controller
Part #: SI3459-B02-IMR
Octal 802.3at PoE PSE Controller