Microchip Technology PD77728 8-Port PoE PSE Controller/Manager

Microchip Technology PD77728 8-Port PoE PSE Controller/Manager is part of Microchip’s seventh-generation IEEE® 802.3bt-compliant Power over Ethernet (PoE) Power Sourcing Equipment (PSE) family. This device is a fully integrated 8-port PoE controller, and PoE manager with integrated Field Effect Transistor (FET) switches and current sense resistors. Up to 12x devices can be cascaded to provide 48x 4-pair ports. According to IEEE, the device supports PoE Powered Device (PD) detection, classification, power-up, and protection, as well as legacy/pre-standard PD detection. The Microchip Technology PD77728 provides real-time protection through overload, under-load, over-voltage, over-temperature, short-circuit, and enables operation in standalone mode. The device is available in a 56-pin 8mm × 8mm QFN package.

Features

  • Supports IEEE 802.3bt standards
  • Supported PD types
    • Type 1, Type 2 PDs (802.3af, 802.3at)
    • Single-signature (Type 1–4) PDs
    • Dual-signature (Type 3 and 4) PDs
    • Pre-standard (legacy) 4-pair PDs
    • Supports non-compliant and legacy PDs
  • 4x operational modes
    • Controller mode in conjunction with PD77020 PSE Power Management Controller
    • Semi-auto mode
    • Managed auto mode
    • Unmanaged auto mode
  • Device
    • Stand-alone device supports up to 8x 2-pair ports or 4x 4-pair ports and any 4-pair/2-pair combination
    • Per-port integrated FET, sense resistor, and port diode
    • 160mΩ total port resistance
    • ≤2W device power dissipation at full load
    • Two power rails (55V and 3.3V) for maximum power efficiency
    • Guaranteed 4-pair output power of >90W
    • Over Supply Signal (OSS) support
    • AutoClass support
    • Supports fast and perpetual PoE
    • MarkHold function support
    • Host interface through I2C communication
  • Cascade up to 12x devices to support 96x 2-pair ports or 48x 4-pair ports and any 4-pair/2-pair combination
  • Real-Time Protection (RTP)
  • Measurements
    • Per-port voltage and current measurement
    • Accurate main power measurement
  • Surge
    • Surge up to 2kV without additional components per IEC61000-4-5-2014
    • Surge compliance, ITU-T K.21, GR1089, IE61000-4-5-2014, EN55024
      • Up to 10kV per IEC61000-4-5-2014
      • Up to 6kV per ITU-T K.21
  • Physical characteristics
    • –40°C to +85°C ambient temperature range
    • 56-pin 8mm × 8mm QFN package with thermal pad
    • Moisture Sensitivity Level (MSL) 3
    • RoHS compliant

Applications

  • Switches and routers for enterprise, small and medium business, SOHO, and commercial markets
  • Switches for the lighting market
  • PoE injectors

Specifications

  • 47.5W 2-pair power
  • 95W 4-pair power
  • 1.185A maximum current
  • 2.0W maximum power dissipation
  • 0.160Ω typical total channel resistance
  • 50kΩ to 70kΩ port resistance range
  • 47nF to 22nF port capacitance range
  • 100W maximum supported output power
  • 65ms typical inrush time
  • 8 ports

Typical PoE Application

Application Circuit Diagram - Microchip Technology PD77728 8-Port PoE PSE Controller/Manager

Block Diagram

Block Diagram - Microchip Technology PD77728 8-Port PoE PSE Controller/Manager
Published: 2024-06-07 | Updated: 2024-08-29