Conflux‚??An Asynchronous Two-to-One Multiplexor for Time-Division Multiplexing and Clockless, Tokenless Readout
This article describes an independent, selfarbitrating asynchronous two-to-one multiplexor called Conflux. Conflux can be used to implement clockless and tokenless timedivision multiplexing between two sources. This capability can then be used to create a clockless and tokenless aggregate data bus that can be used as a complete asynchronous readout architecture for a chip, a part of a chip, or an entire multichip system. Conflux utilizes a classic, four-phased asynchronous handshake on both of its input ports as well as on its output port. Asynchronous Request is bundled with Data to ensure consistent propagation delay. The Request is also implemented as a differential signal to account for propagation delay differences between logical ones and zeros. Arbitration between the two Conflux input streams is accomplished by three Set‚??Reset Latches. Finally, Conflux cells were used successfully to implement the readout architecture of the FCP130 prototype chip. Tests indicate single Conflux stage delays of 1.8 ns and a bandwidth of approximately 11 Gb/s in 130-nm CMOS.
Asynchronous circuits, multiplexing, timedivision multiplexing