LAN9420/LAN9420i is a full-featured, Fast Ethernet controller which allows for the easy and cost-effective integration of Fast Ethernet into a PCI-based system. LAN9420/LAN9420i consists of a PCI Local Bus Specification Revision 3.0 compliant interface, DMA Controller, Ethernet MAC, and 10/100 Ethernet PHY.

LAN9420/LAN9420i provides full IEEE 802.3 compliance and all internal components support full/half-duplex 10BASE-T, 100BASE-TX, and manual full-duplex flow control. The descriptor based scatter-gather DMA supports usage of zero-copy drivers, effectively increasing throughput while decreasing Host load. The integrated IRQ deassertion timer allows a minimum IRQ deassertion time to be set, providing reduced Host load and greater control over service routines. Automatic 32-bit CRC generation/checking, automatic payload padding, and 2K jumbo packets (2048 byte) are supported.

Microchip's complimentary and confidential [MicroCHECK](https://www.microchip.com/en-us/support/design-help/design-check-services) design review service, which offers insight from the initial concept to the final PCB layout, is available to customers who are using our products in their projects. You can confidently submit your design materials in a secure and private setting, and our expert engineers will provide individualized feedback to enhance your design. MicroCHECK design review service is subject to Microchip's [Program Terms and Conditions](https://www.microchip.com/en-us/support/design-help/design-check-services/design-check-services-program-terms-and-conditions) and requires a myMicrochip account.