622 Mbit/s board-to-board link in 0.5 μm CMOS technology

High speed digital processing chips demand also high speed interconnections. On-board communication with a limited distance have already been realised. However in this paper an inter board communication over a relative long distance is presented. To minimise signal reflections in this kind of communication networks a special termination circuit has been developed. This impedance termination can be tuned to match the characteristic impedance of the transmission wire. Using this termination circuit a driver and receiver are designed. Transmission rates up to 800 Mbit/s have been measured. The two boards are connected to each other with a twin ax shielded wire plugged in the backplane connector of the two PCBs. To allow integration with the digital processing chips a standard CMOS process is used to realise the driver and receiver chips