Integrated SCSI and ethernet controller on a PCI local bus

An apparatus comprising a SCSI controller and an Ethernet controller integrated onto a single integrated circuit chip, wherein the SCSI and Ethernet controller include digital control circuitry coupled to buffers, and the Ethernet controller includes analog circuitry, wherein the circuitry on the integrated circuit chip is configured to limit noise generated in the analog circuitry by signals in the digital control circuitry, wherein the integrated circuit chip includes a data input for receiving a data signal and an output, wherein each of the buffers comprise:

• transistor pairs, each transistor pair having a pull up transistor and a pull down transistor, wherein each of the pull up transistors has a source to drain path connected between VDD and the buffer output, and wherein each of the pull down transistors has a source to drain path connected between VSS and the buffer output;
• and
• delay elements connected in series, wherein a first one of the delay elements has an input forming the data input of the buffer, and wherein each of the delay elements has an output coupled to a gate of each of the pull up and pull down transistors of one of the transistor pairs.

An apparatus comprising a SCSI controller and an Ethernet controller integrated onto a single integrated circuit chip, wherein the SCSI and Ethernet controller include digital control circuitry coupled to buffers, and the Ethernet controller includes analog circuitry, wherein circuitry on the integrated circuit chip is configured to limit noise generated in the analog circuitry by signals in the digital control circuitry, wherein the analog circuitry is located separate from the digital control circuitry and the buffers.

An apparatus comprising a SCSI controller and an Ethernet controller integrated onto a single integrated circuit chip, wherein the SCSI and Ethernet controller include digital control circuitry coupled to buffers, and the Ethernet controller includes analog circuitry, wherein circuitry on the integrated circuit chip is configured to limit noise generated in the analog circuitry by signals in the digital control circuitry, wherein current density in the digital control circuitry increases in a direction away from the analog circuitry.

An apparatus comprising a SCSI controller and an Ethernet controller integrated onto a single integrated circuit chip, wherein the SCSI and Ethernet controller include digital control circuitry coupled to buffers, and the Ethernet controller includes analog circuitry, wherein circuitry on the integrated circuit chip is configured to limit noise generated in the analog circuitry by signals in the digital control circuitry, wherein the circuitry on the integrated circuit chip comprises:

• power distribution networks, including a first network connected to distribute power to the analog circuitry, a second network connected to distribute power to the digital control circuitry and a third network connected to distribute power to the buffers;
• and
• silicon control rectifiers (SCRs) connected between the power distribution networks, each SCR for sensing when a voltage difference between two of the power distribution networks exceeds a predefined limit, and for forming a conductive path between the two networks when the predefined limit is reached.