Reference voltage distribution for multiload I/O systems

According to an embodiment of the invention a circuit that is to be coupled to a reference voltage line. The circuit includes a noise coupling circuit that is to couple noise from the circuit to reference voltage line based upon whether a driver is driving a data line. Noise is driven onto the reference voltage line for high and low signals, and substantially matches that on the data line as it is generated in the same chip. Also provided is at least one reference voltage keeper (221,226,231) to maintain the voltage on the reference line either when no data is being driven on to the data line or during a switchover between driver circuits. Can be used with CMOS circuitry.