Single Chip Adapter
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-01
This article describes a single-chip implementation of the transmission line analog interface for the IEEE 802.5 Token Ring Local Area Network. The functional implementation of this interface on a single chip is made possible by using three on-chip noise-isolation techniques. First, the analog and digital grounds were separated and brought out to different pins on the module. Second, cascode current switch logic was used to minimize noise on the voltage and ground buses. Third, highly sensitive circuits were physically isolated from the high power and digital circuits. The combination of these design "techniques" enabled the circuitry to be contained on a single chip. A block diagram of the chip is shown in the figure.