LAN91C111-NU

Controllers Overview

The LAN91C111-NU is a single-chip Ethernet controller integrating MAC and PHY layers for 10/100 Mbps networks. It operates on a 3.3V supply with 5V tolerant I/O buffers. The device features an 8 Kbyte internal FIFO buffer, supports 8, 16, and 32-bit host interfaces (ISA/EISA), and includes auto-negotiation capabilities. It utilizes a 25 MHz reference clock and provides MII connectivity. The component is housed in a 128-pin TQFP package and is rated for commercial temperature ranges from 0°C to 70°C.

Controllers Feature Summary

• Integrates IEEE 802.3/802.3u compliant MAC and PHY layers into a single mixed-signal device.
• Supports flexible host bus interfaces including ISA, EISA, and various embedded processor architectures.
• Includes internal 8 Kbyte memory for transmit and receive operations managed by a hardware MMU.
• Features on-chip wave shaping and adaptive equalization eliminating the need for external filters.

Controllers Applications

• Embedded system network adapters
• Industrial automation controllers
• Information appliance networking modules

Controllers Procurement Notes

Verify the specific suffix 'NU' corresponds to the 128-pin TQFP package variant when sourcing. Confirm that the commercial temperature grade meets the operational requirements of the target environment. Ensure compatibility with the required host bus interface width and voltage levels before finalizing procurement.

Controllers Selection Notes

Select this component for designs requiring integrated MAC/PHY functionality without external transceivers. Consider the 128-pin TQFP footprint constraints during PCB layout. Verify that the host processor supports the necessary asynchronous or synchronous bus protocols for data transfer.

Controllers Part Context

This part belongs to the LAN91C111 family of Fast Ethernet controllers originally developed by SMSC and now manufactured by Microchip Technology. It serves as a third-generation solution for embedded applications, offering software compatibility with previous LAN9000 series products while providing enhanced integration and performance.

Controllers Replacement Considerations

LAN91C111I-NU: Industrial temperature range variant (-40°C to 85°C).

Controllers FAQ

Does the LAN91C111-NU require external filters for 100Base-TX operation?

No, the device includes internal output wave shaping circuitry and on-chip filters, eliminating the need for external filters typically required in 100Base-TX applications.

What is the maximum frequency for the local bus clock (LCLK)?

The maximum frequency for the LCLK pin is 50 MHz in VL Bus mode, limited to 8.33 MHz for EISA slave DMA burst mode.