Microchip Technology LAN8831 Gigabit Ethernet Transceivers
Microchip Technology LAN8831 Gigabit Ethernet Transceivers with GMII/MII/RGMII are fully integrated triple-speed (10BASE-T/100BASE-TX/1000BASE-T) Ethernet physical-layer transceivers. The devices are designed for transmitting and receiving data on standard CAT-5, CAT-5e, and CAT-6 unshielded twisted pair (UTP) cables.The Microchip LAN8831 Gigabit Ethernet Transceivers provide the industry-standard GMII/MII (Gigabit Media Independent Interface/Media Independent Interface) for contact to GMII/MII MACs in Gigabit Ethernet processors and switches for data transfer at 1000Mbps or 10/100Mbps. Additionally, an optional RGMII (Reduced Gigabit Media Independent Interface) mode is supplied, enabling the LAN8831 to deliver additional GPIOs.
The LAN8831 has a simplified board layout and decreased board cost by implementing on-chip termination resistors for the four differential pairs and integrating an LDO controller to drive a low-cost MOSFET to supply the core voltage. The LAN8831 has diagnostic features to promote system bring-up and debugging in production testing and product deployment.
The LAN8831 is housed in a 64-pin, RoHS-compliant VQFN package.
Features
- Single-chip 10/100/1000Mbps Ethernet transceiver suitable for IEEE 802.3 applications
- GMII/MII standard interface with 3.3V/2.5V/1.8V tolerant I/Os
- RGMII with 3.3V/2.5V/1.8V tolerant I/Os
- RGMII timing supports on-chip delay according to RGMII version 2.0 with programming options for an external delay and making adjustments/corrections to TX and RX timing paths
- Auto-negotiation to automatically select the highest link-up speed (10/100/1000Mbps) and duplex (Half/Full)
- On-chip termination resistors for the differential pairs
- On-chip LDO controller to support single 3.3V supply operation
- Jumbo frame support up to 16KB
- 125MHz Reference clock output
- Energy-detect power-down mode for reduced power consumption when the cable is not attached
- Energy Efficient Ethernet (EEE) support with Low-Power Idle (LPI) mode and clock stoppage for 100BASE-TX/1000BASE-T and transmit amplitude reduction with 10BASE-Te option
- Wake-On-LAN (WOL) support with robust Custom-packet detection
- Programmable LED outputs for link, activity, and speed
- LinkMD® TDR-based cable diagnostic to identify faulty copper cabling
- Signal Quality Indication
- Parametric NAND tree support to detect faults
- Between chip I/Os and board
- Loopback modes for diagnostics
- Automatic MDI/MDI-X crossover to detect and correct pair swap at all speeds of operation
- Automatic detection and correction of pair swaps, pair skew, and pair polarity MDC/MDIO management interface for PHY register configuration
- Interrupt pin option
- Power-down and power-saving modes
- Operating voltages
- Core (VDD, VDDAL, VDDAL_PLL)
- 3.3V, 2.5V, or 1.8V VDD I/O (VDDIO)
- 3.3V or 2.5V Transceiver (VDDAH)
- Available in commercial (0°C to +70°C) and extended industrial (-40°C to +105°C) temperature ranges
- 64-pin VQFN (8mm × 8mm) package
Applications
- Industrial control
- Laser/network printer
- Network Attached Storage (NAS)
- Network server
- Broadband gateway
- Gigabit SOHO/SMB router
- IPTV
- IP Set-top box
- Game console
- IP Camera
- Triple-Play (Data, voice, video) media center
- Media converter
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